a. Ethical concerns surrounding AI [2]

AI raises several ethical concerns:

• Bias and discrimination — systems trained on skewed data can favour or penalise particular groups in hiring, lending or policing.
• Privacy — AI collects and analyses vast personal data, often without meaningful consent.
• Accountability — when an autonomous system causes harm, it is hard to fix responsibility on a person.
• Autonomy and jobs — automated decisions and automation reduce human control and displace workers.
• Autonomous weapons and misuse — AI can be used for surveillance or lethal force without human judgement.

b. How can we mitigate bias in AI systems? [2]

• Use diverse, representative and balanced datasets, and audit them for missing or stereotyped groups.
• Pre-process, in-process and post-process the model: reweight or resample data, add fairness constraints in training, and correct biased outputs.
• Ensure diverse development teams and third-party audits with fairness metrics (demographic parity, equal opportunity).
• Keep humans in the loop for high-stakes decisions and allow appeal against automated outcomes.

c. Steps to ensure ethical development and use of AI [2]

• Frame and enforce ethical guidelines and regulation (transparency, fairness, privacy, accountability).
• Build in privacy by design, informed consent and data-protection compliance.
• Make systems explainable and auditable, with clear responsibility and redress mechanisms.
• Promote ethics education and awareness among developers and users, and encourage public debate.
• Establish oversight bodies and independent review before deployment in sensitive areas.

d. Major argument of the passage [4]

The passage argues that artificial intelligence, though powerful and beneficial, is not ethically neutral: because it is built from human data and human choices, it can reproduce bias, invade privacy and escape accountability. Therefore its development and use must be guided by clear ethical principles — fairness, transparency, privacy and responsibility — enforced through guidelines, audits and human oversight. In short, the benefits of AI can be enjoyed only if society deliberately governs how it is built and deployed.

a. Impact of human activities on the environment (with reference to Gordon Rattray Taylor's "Pollution and Super-pollution")

Gordon Rattray Taylor, in his essay "Pollution and Super-pollution," argues that human beings have become the most destructive geological force on the planet. Unlike natural pollution, which the biosphere can absorb and recycle, modern human activity produces "super-pollution" — pollutants released in such volume and of such unnatural chemical complexity that nature's self-cleansing mechanisms fail. The impact can be discussed under the following heads.

1. Air pollution and the poisoning of the atmosphere. Taylor points out that the burning of fossil fuels in factories, homes and motor vehicles pours carbon dioxide, sulphur dioxide, nitrogen oxides, carbon monoxide and particulate matter into the air. Carbon dioxide traps heat and threatens a greenhouse warming of the climate; sulphur dioxide and nitrogen oxides return to the earth as acid rain, killing forests and acidifying lakes. The example of London's killer smog and the steady rise of CO₂ in the atmosphere are used to show that what was once a local nuisance has become a global threat.

2. Water pollution. Industrial effluents, untreated sewage, detergents and agricultural run-off carrying fertilizers and pesticides are dumped into rivers, lakes and seas. Taylor cites the example of rivers so loaded with organic waste that oxygen levels fall and fish die, and of lakes becoming "dead" through eutrophication caused by phosphate-rich detergents. Mercury and other heavy metals from industry accumulate in fish and reach human beings through food, causing Minamata-type poisoning.

3. Soil pollution and the abuse of chemicals. The heavy use of pesticides such as DDT and chemical fertilizers leaves persistent residues in the soil. Taylor stresses that these substances are non-biodegradable — they do not break down but travel through the food chain and concentrate in the fatty tissues of birds, animals and human beings. This is the phenomenon of biological magnification, which he treats as the essence of super-pollution. Soil is also degraded by over-cultivation, deforestation and careless mining.

4. Radioactive and other new pollutants. Nuclear tests, nuclear power stations and the disposal of radioactive waste add a wholly new and dangerous class of pollution. Taylor warns that radioactive isotopes like strontium-90 enter the food chain, lodge in bones and cause cancer and genetic damage. Similarly, noise, chemical wastes and non-degradable plastics are pollutants for which nature has no remedy.

5. Destruction of the ecological balance. Human activities such as deforestation, large dams, land reclamation and urbanisation destroy habitats and drive species to extinction. Taylor stresses that every species is a link in a delicate web; the loss of one link weakens the whole system. The clearing of tropical forests, for example, reduces rainfall, causes soil erosion and destroys the home of countless organisms.

6. Population growth and over-consumption. Taylor links pollution to the explosive growth of human population and to rising standards of consumption. More people demand more food, fuel and goods, and therefore produce more waste. The rich nations, with a small fraction of the world's population, consume a disproportionate share of resources and generate most of the industrial pollution.

Conclusion. Taylor's central message is that pollution is no longer a local problem to be solved by dilution or by shifting it elsewhere. Because the earth is a closed system, pollutants return to us through air, water and food. The remedy lies in controlling population, reducing wasteful consumption, treating wastes before discharge, and adopting technologies that work with nature rather than against it. Human beings must recognise that they are part of the environment, not its masters.

b. Fundamental limits on the efficiency of solar energy conversion (with reference to H. A. Bethe's "The Cost of Solar Heat")

In "The Cost of Solar Heat," H. A. Bethe examines solar energy as a substitute for fossil fuels and shows that, although sunlight is abundant and free, its conversion into useful work is restricted by certain fundamental physical limits. These limits are of two kinds: thermodynamic limits and practical/economic limits.

1. The thermodynamic (Carnot) limit. Any device that converts heat into mechanical work must obey the second law of thermodynamics. If heat is collected at absolute temperature T₁ and rejected to the surroundings at temperature T₂, the maximum possible efficiency is the Carnot efficiency:

$\eta_{max} = \frac{T_1 - T_2}{T_1} = 1 - \frac{T_2}{T_1}$

Since the ambient temperature T₂ is fixed at about 300 K, the only way to raise efficiency is to raise T₁. But solar collectors that reach very high temperatures lose heat rapidly by radiation and convection, and require expensive concentration and insulation. Thus there is a hard ceiling on efficiency that no engineering skill can remove.

2. The dilute nature of sunlight. Solar energy arrives at the earth's surface at a low intensity — roughly 1 kW per square metre at best, and much less on cloudy days or in temperate latitudes. Because the energy is spread thinly, large collecting areas are needed. Bethe emphasises that this dilution is a fundamental limit: it cannot be overcome except by concentrating the rays with mirrors or lenses, which adds cost and complexity and works only in regions of strong direct sunlight.

3. The spectral and band-gap limit of photovoltaic cells. A solar cell can convert only those photons whose energy exceeds the band gap of the semiconductor. Photons of lower energy are wasted as heat, while photons of much higher energy lose their excess as heat when the electron falls back to the band edge. For a single-junction cell this gives the Shockley–Queisser limit of about 33 % for an ideal cell, and practical cells achieve far less. Bethe notes that this loss is inherent in the physics of the material and cannot be engineered away in a simple cell.

4. Intermittency and storage losses. Sunlight is available only during the day and is reduced by clouds and seasons. Energy collected in excess must be stored (in batteries, pumped water, or thermal mass) for use at night or in winter. Every storage and reconversion step involves further losses, so the overall efficiency of a solar system, from incident sunlight to delivered work, is much lower than the efficiency of the collector alone.

5. Economic limit — the "cost" in the title. Bethe's central argument is that the real limit is cost, not abundance. To collect a large amount of energy one needs vast areas of collectors, mirrors, piping and storage, together with maintenance. The capital cost per unit of delivered energy remains high compared with fossil fuels. Thus even where the physical efficiency is acceptable, the economic efficiency may not be.

6. Comparison with photosynthesis and other natural limits. Bethe also compares artificial conversion with natural photosynthesis, whose efficiency is only about 1–2 % of incident sunlight. This shows how severe the natural limits are and how difficult it is to improve on them.

Conclusion. The fundamental limits on solar energy conversion are: the Carnot limit set by the second law, the low intensity of sunlight, the band-gap/spectral limit of photovoltaic materials, losses due to intermittency and storage, and above all the high capital cost of collection. Bethe concludes that solar energy can make only a limited contribution unless these limits are met by cheap materials, efficient concentrators and large-scale storage.

The correct order is:

iii. Bronowski says that man is a part of nature. i. This is the statement which has made Western man lose his self-assurance. iv. He lost his self-assurance because this statement means that man is not unique. v. But man wants to feel unique and immortal. ii. He also wants to feel that he has been, from the beginning, larger than nature.

The paragraph reads:

Bronowski says that man is a part of nature. This is the statement which has made Western man lose his self-assurance. He lost his self-assurance because this statement means that man is not unique. But man wants to feel unique and immortal. He also wants to feel that he has been, from the beginning, larger than nature.

(i) An atlas will show you the location of the cities you are looking for.

(ii) Some people are friendly while others are not.

(iii) There was once a beggar who lived in the capital city of Alexander's great empire.

Reasons: "atlas" is a singular countable noun beginning with a vowel sound, so an; "cities you are looking for" is made specific by the clause, so the; "some" contrasts with "others"; "beggar" is a first mention, so a; "capital city of Alexander's empire" is one particular city, so the.

Technological advancements have transformed society and reshaped the way we live. In the past, communication across long distances took days or even weeks, but today a message reaches the other side of the world in seconds through mobile phones and the internet. Similarly, medical technology has raised life expectancy by enabling early diagnosis and effective treatment of diseases that were once fatal. Education has also changed, as students can now attend online classes and access vast libraries of information from their homes. Even daily tasks such as banking, shopping and paying bills are performed with a few taps on a screen. These changes have made life faster, easier and more connected, though they have also created new challenges like dependence on devices and concerns about privacy. Thus, technology has deeply reshaped the way we live.

Topic chosen: (a) The impact of climate change on biodiversity

Outline

1. Introduction — definition of climate change and biodiversity; thesis: climate change is now one of the most powerful drivers of biodiversity loss.
2. Background — how the climate has shifted since industrialisation; why species evolved to fit narrow climatic ranges; the point of origin of the argument (rising greenhouse gases → shifting temperature and rainfall belts).
3. Discussion I — Direct impacts — range shifts, phenological mismatch, coral bleaching, extinction risk.
4. Discussion II — Indirect impacts — habitat fragmentation, invasive species, pests and pathogens, ecosystem service loss.
5. Conclusion — summary, the human stake in biodiversity, and the need for mitigation plus protected corridors.

Essay

1. Introduction

Climate change refers to the long-term alteration of temperature, rainfall, wind and sea-level patterns, driven mainly by the accumulation of greenhouse gases from burning fossil fuels. Biodiversity is the variety of life at three levels: genetic variety within species, the number of species, and the range of ecosystems. These two are linked because every species is adapted to a particular climate envelope — a set of temperature, moisture and seasonal conditions within which it can survive and reproduce. When that envelope moves, species must move, adapt or die. This essay argues that climate change has become one of the most powerful drivers of biodiversity loss, acting both directly on organisms and indirectly by reshaping the habitats and interactions on which they depend.

2. Background and Point of Origin of the Argument

The argument begins with a simple physical fact: the atmosphere now traps more heat than at any time in the recent geological past. Global mean surface temperature has risen by roughly 1.1 °C above the pre-industrial level, and the rise is faster than most natural climate shifts in the last ten thousand years. Because temperature and rainfall determine where plants can grow, the climatic belts of the planet are sliding — upward on mountains and poleward at lower elevations — at a speed of several kilometres per decade. Species, however, cannot always keep pace. Trees may take centuries to migrate, while the climate zone they need may shift within a single human lifetime. This mismatch between the speed of climate change and the speed of biological response is the origin of the crisis. It is worsened by the fact that human land use — farms, roads, cities — has already fragmented the landscape, so the escape routes that species would naturally use are blocked.

3. Discussion I: Direct Impacts on Species and Ecosystems

The most visible direct impact is range shift. Warm-adapted species move towards the poles or upslope, while cold-adapted species are pushed into shrinking refuges. On tropical mountains, species such as the Himalayan pika and several high-altitude rhododendrons have nowhere further to climb, a phenomenon called the "escalator to extinction". In the ocean, warming water forces fish and plankton to migrate poleward, disturbing fisheries.

A second direct impact is phenological mismatch — the uncoupling of seasonal timing between species that depend on each other. In Europe, oak leaves now unfold earlier, but the winter moth caterpillars that feed on them and the migratory birds that feed on the caterpillars have not shifted at the same rate. The chicks hatch after the food peak has passed, and breeding success falls. In Nepal, earlier snowmelt and flowering times affect the timing of honey hunting and the migration of birds through the Koshi wetlands.

A third is coral bleaching. Corals live within 1–2 °C of their thermal limit. A prolonged heat wave makes them expel their symbiotic algae, turning the reef white. The Great Barrier Reef has suffered repeated mass bleaching events since 1998, and reefs in the Indian Ocean and the Gulf of Mannar have suffered similarly. Since reefs shelter about a quarter of all marine species, bleaching is a biodiversity collapse in miniature.

Finally, climate change raises extinction risk. The IPCC estimates that with 1.5 °C of warming, about 6 % of insects, 8 % of plants and 4 % of vertebrates lose over half their geographic range; at 3 °C these figures rise sharply. Species with small populations, narrow ranges and low mobility — amphibians, island birds, alpine plants — are the most vulnerable.

4. Discussion II: Indirect Impacts and Feedbacks

Indirect effects are often more damaging than direct warming itself. Habitat fragmentation is the first: as suitable climate space breaks into isolated patches, populations become small and inbred, and local extinction becomes likely. A species may survive the heat but not the isolation.

Second, climate change redistributes invasive species and pests. Warmer winters allow mosquitoes, bark beetles and crop pests to survive in new areas. In Nepal, the mosquito Aedes aegypti, a vector of dengue, has spread into hill districts that were previously too cool. Bark beetles have killed vast areas of conifer forest in North America, converting carbon sinks into carbon sources.

Third, pathogens and disease spread more easily under stress. Amphibians weakened by heat and drought are more susceptible to the chytrid fungus, which has already driven dozens of species to extinction worldwide.

Fourth, there is a feedback loop with ecosystem services. Loss of forest cover reduces carbon storage, which accelerates warming, which causes further forest dieback — a self-reinforcing cycle. Pollinator decline, partly driven by climate-related mismatches, threatens crop yields and therefore food security. In the Hindu Kush–Himalaya region, glacier retreat changes river flow, affecting freshwater species and the millions of people who depend on them.

5. Conclusion

Climate change affects biodiversity in two ways: directly, by exceeding the thermal and moisture limits of species and disrupting the timing of their life cycles; and indirectly, by fragmenting habitats, spreading invasive species and pathogens, and weakening the ecosystem services on which both wildlife and people depend. The evidence from coral reefs, mountain tops and migratory flyways all points in the same direction — the faster the climate changes, the fewer species can keep up. Because biodiversity underpins food, water, medicine and climate stability, its loss is not merely an environmental problem but an economic and social one. The response must therefore be twofold: aggressive mitigation to slow warming, and large-scale adaptation — protected areas, wildlife corridors, restoration of degraded land — to give species the room and time to move. Only by treating climate and biodiversity as a single, connected crisis can either be solved.

a) Features of the pre-scientific world [2]

In the pre-scientific world, people believed that events could be made to go as they wished by prayer and humility rather than by knowledge of natural laws. The power believed to come from prayer was thought to be real, but it was unreliable — one could never be sure whether the prayer would be favourably heard in heaven. It also had recognized limits: it would have been impious to ask too much. Finally, the pre-scientific world rested on faith — people were told that faith could remove mountains, but no one actually believed it.

b) Gist of the text [2]

The passage contrasts the power of prayer with the power of science. Prayer and humility, the old way of trying to control events, gave a power that was uncertain and strictly limited. Science, by contrast, gives power through the knowledge of natural laws, and this power is far greater and far more reliable. Unlike the power of prayer, the power of science has no known limits. The old claim that faith could remove mountains was never believed, but the modern claim that atomic bombs can remove mountains is believed by everyone — showing how real and credible scientific power has become.

c) Deductive logical order in the passage [2]

Yes, the passage shows a clear deductive logical order. It moves from a general contrast (the pre-scientific way of prayer versus the scientific way of knowledge of natural laws) to supporting reasons (prayer is unreliable and limited; science is reliable and unlimited), and finally to a concrete illustration that clinches the argument (faith removing mountains was never believed, but atomic bombs removing mountains is believed by all). The reasoning proceeds from the general principle to particular evidence, which is the pattern of deduction.

d) Own title to the paragraph [2]

A suitable title would be: "The Unlimited Power of Science versus the Limited Power of Prayer" (or, more briefly, "Science: The Limitless Power").

e) Should there be God in this Godless universe? [2]

This is a matter of personal belief, but a reasoned answer can be given. If "God" means a being who can be persuaded by prayer to suspend natural laws, then the growth of science leaves little room for such a God, since events are now explained by natural laws rather than by divine favour. However, many argue that a Godless universe of pure natural law offers no basis for meaning, morality or hope, and that belief in God is still needed to give purpose to human life. In my view, science and a belief in God need not exclude each other: science can explain how the universe works, while belief in God can address why it exists and how we should live — so a reasonable place for God remains even in a scientifically explained universe.

How Human Beings Change the Environment (with reference to "Pollution and Super Pollution")

Introduction Human beings are the most powerful agents of environmental change on the earth. Unlike other living creatures, humans do not merely adapt to nature; they alter it to satisfy their needs and comforts. Since the Industrial Revolution, and especially in the last hundred years, this interference has grown so rapid and so wide that it has disturbed the natural balance of air, water, land and life itself. The essay "Pollution and Super Pollution" shows that what we call "development" has, in practice, often meant the slow poisoning of the environment.

Ways in which human beings change the environment The author points out that human beings change the environment mainly through the following activities:

1. Rapid population growth and urbanisation. More people need more food, fuel, houses and transport. Cities expand, forests and farmland are swallowed up, and wastes pile up faster than nature can absorb them.

2. Industrialisation. Factories pour smoke, dust, sulphur dioxide and other gases into the air, and discharge chemical effluents, acids and hot water into rivers and lakes. Industrial accidents and careless disposal turn whole areas into dead zones.

3. Burning of fossil fuels. Coal, petroleum and natural gas burnt in homes, factories and power stations release carbon dioxide, carbon monoxide, nitrogen oxides and soot. This causes air pollution, acid rain and global warming.

4. Deforestation and destruction of natural habitats. Trees are felled for timber, fuelwood and farmland. Forests that once purified the air, held the soil and brought rain are lost, leading to floods, landslides and drought.

5. Modern agriculture. Chemical fertilisers, insecticides and pesticides are used heavily to raise yields. These poison the soil and water, kill useful insects and birds, and leave residues in our food.

6. Dumping of domestic and industrial waste. Sewage, garbage, plastics and non-biodegradable materials are thrown into rivers, ponds and open land, causing water and soil pollution and spreading disease.

7. Transport and noise. Motor vehicles and aircraft release exhaust fumes and create noise; loudspeakers, machines and traffic add to noise pollution, which harms hearing and mental health.

8. Radioactive and nuclear pollution. Nuclear tests, nuclear power plants and the dumping of radioactive waste leave long-lived poisons that cannot be destroyed and that cause cancer and genetic damage.

9. Over-exploitation of resources. Forests, fisheries, minerals, groundwater and fossil fuels are used faster than they can be renewed, so the environment loses its capacity to recover.

Super pollution The author's special point is that some pollutants are "super pollutants". Ordinary pollution can be diluted or broken down by nature, but super pollution cannot. Substances such as DDT, plastics, heavy metals (mercury, lead) and radioactive isotopes remain in the environment for decades or centuries. They enter the food chain, become more concentrated at each level, and finally reach human beings, causing cancer, deformity and slow death. Thus super pollution is pollution that nature itself cannot cure.

Conclusion Human beings change the environment by clearing forests, building cities and industries, burning fuels, using chemicals and dumping wastes. The essay warns that unless we control our greed and careless habits, ordinary pollution will turn into super pollution and make the earth unfit for human life.

(b) Major ideas of "Science and Survival" by Barry Commoner, and whether his argument is worth considering

Major ideas of the essay

Barry Commoner's essay "Science and Survival" (from his 1966 book Science and Survival) examines the growing gap between scientific knowledge and its social consequences. Its major ideas are:

1. Science has become a double-edged weapon. Modern science gives us great power over nature, but the same power can destroy us. Nuclear weapons, chemical pesticides and pollution are examples of knowledge used harmfully.

2. The separation of science from its consequences. Commoner argues that scientists often treat science as a pure, value-free search for truth and hand over its application to politicians, industry and the military. This separation is dangerous, because the responsibility for how knowledge is used is pushed away from those who create it.

3. The "technological gap" or "social gap." We adopt new technologies very fast, but our social, moral and political institutions develop very slowly. This mismatch means we use powerful tools before we understand their long-term effects.

4. The ecological crisis. Commoner stresses that nature is an interconnected system. Human beings are part of this system, not masters above it. Pollution and the careless use of technology break the natural cycles and finally harm human beings themselves. (This idea later became his famous "Four Laws of Ecology.")

5. The need for social control of science. He does not ask us to stop science. He asks us to make science accountable to society — to plan technology democratically, to assess risks before use, and to let the public take part in decisions that affect their survival.

6. Survival depends on wisdom, not only knowledge. The title itself carries the message: science alone cannot save us; we need social responsibility and moral judgement along with scientific skill.

Is his argument worth considering?

Yes, his argument is definitely worth considering, and it is even more relevant today than when it was written.

• It is realistic, not anti-science. Commoner accepts the benefits of science but warns against blind faith in it. This balanced view is sensible.
• The problems he pointed out still exist. Climate change, air and water pollution, nuclear weapons, genetic engineering and artificial intelligence all show the same pattern — powerful knowledge used without enough social control.
• His solution is practical. Environmental impact assessment, public debate, regulation and international agreements are all attempts to do what he asked: bring science under social responsibility.
• It teaches moral responsibility. Scientists, engineers and citizens all share the duty to ask not only "Can we do this?" but "Should we do this?"

Conclusion

Commoner's central message — that science must be guided by social and moral responsibility if humanity is to survive — is a warning that remains valid. His argument is therefore well worth considering, both for students of science and for every responsible citizen.

Fingerprints provide clues about person's health**.**

(ii) Have you ever been finger-printed**?**

(iii) Many people wonder if fingerprints are reliable**.**

(iv) We won**!**

(v) Children's fingerprints vanish more quickly**.**

(b) Antonyms [2.5]

Outline of a Composition: "Students' Protest — Purposeful or Harmful?"

1. Introduction

• Definition of students' protest: a collective expression of dissent by students against injustice, policy or authority.
• Historical context: student movements have shaped many democratic changes worldwide and in Nepal (e.g., 1990 and 2006 movements).
• Thesis statement: Students' protest is purposeful when peaceful, issue-based and disciplined; it becomes harmful when violent, politically exploited, or aimless.

2. Protest as Purposeful

• Voice against injustice: students are conscious citizens who expose corruption, inequality, and misuse of authority.
• Agent of social and political reform: many democratic freedoms and educational reforms were achieved through student movements.
• Awareness and unity: protests educate the public, build solidarity, and develop leadership and civic responsibility.
• Accountability: peaceful protest pressures authorities to correct wrong policies and address genuine grievances.

3. Protest as Harmful

• Loss of study time: prolonged strikes, closures, and boycotts damage academic careers and institutional discipline.
• Violence and destruction: vandalism, clashes, and injuries harm public property, lives, and the image of students.
• Political exploitation: students are often used as tools by parties and vested interests for their own agendas.
• Anarchy and disrespect for law: if protests ignore legal procedures, they weaken the rule of law and set a bad precedent.

4. Balanced View / Suggestions

• Protest should be peaceful, lawful, and issue-based, not personal or partisan.
• Dialogue, negotiation, and student unions should be the first means; protest only as a last resort.
• Students must keep academic responsibility and social responsibility in balance.

5. Conclusion

• Protest is neither wholly purposeful nor wholly harmful; its value depends on intent, method, and outcome.
• Peaceful, constructive protest is a democratic right and a force for good; violent or exploited protest is destructive.
• Students should protest with wisdom, discipline, and a clear, just cause.

Three-Day Science Exhibition in Your Campus

A Report

Kathmandu, [Date] — A three-day science exhibition was held at [Campus Name], [Location], from [start date] to [end date]. The exhibition was organised by the Science Students' Society in coordination with the Campus Administration, with the aim of encouraging scientific curiosity, creativity and practical learning among students. The event was inaugurated by the Campus Chief amid a gathering of teachers, students and invited guests.

The exhibition featured more than sixty stalls, each presenting models, charts and working demonstrations prepared by students of the first and second years. The exhibits covered a wide range of subjects, including physics, chemistry, biology, mathematics, computer science and environmental science. Popular attractions included a working model of a hydroelectric plant, a solar-powered water pump, a simple robot, a model of the human respiratory system, and demonstrations of titration and chemical reactions. Several stalls also displayed low-cost, locally made technologies such as a smokeless stove, a rainwater harvesting system and a biogas plant model. Each stall was managed by student volunteers who explained the working principles of their models to the visitors.

The exhibition drew a large number of visitors, including students from nearby schools and colleges, teachers, parents and members of the local community. Guest judges from [University/Institute Name] evaluated the exhibits on the basis of originality, scientific understanding, presentation and usefulness. The programme also included short talks by teachers on topics such as climate change, renewable energy and the responsible use of technology. On the final day, prizes were awarded to the three best exhibits. The first prize went to the model of a solar-powered water pump, the second to the biogas plant model, and the third to the working model of a simple robot. Certificates of participation were distributed to all the participants.

The exhibition concluded successfully on [end date] with a vote of thanks by the president of the Science Students' Society. The event proved highly beneficial for the students, as it gave them an opportunity to apply their theoretical knowledge in practice, to develop skills of presentation and teamwork, and to build confidence. It also helped to spread scientific awareness in the local community. The organisers expressed their gratitude to the campus administration, teachers and sponsors for their support, and announced that the exhibition would be held every year on a larger scale.

Science and Society

Science and society have always been closely connected, each shaping and reshaping the other. Science is the systematic study of nature through observation, experiment and reasoning, while society is the organised community of people who live together. The knowledge produced by science has transformed the way people live, work, communicate and think. At the same time, the needs, values and problems of society determine the direction in which science develops. This two-way relationship has made science one of the most powerful forces in modern life.

The contribution of science to society is visible in every field of human activity. In medicine, the discovery of vaccines, antibiotics and modern surgical techniques has saved millions of lives and increased life expectancy. In agriculture, improved seeds, chemical fertilisers and irrigation technology have increased food production and reduced hunger. In communication and transport, the invention of the telephone, the internet, aeroplanes and electric vehicles has brought distant places closer and made the world a global village. In industry, machines and automation have increased production and created new forms of employment. In short, science has provided society with comfort, health, speed and efficiency that earlier generations could hardly imagine.

However, the same science that has brought progress has also created serious problems. Industrialisation and the reckless use of fossil fuels have caused air and water pollution, deforestation and climate change. The invention of nuclear weapons and chemical weapons has made war far more destructive than before. The misuse of antibiotics has produced drug-resistant bacteria, and the excessive use of pesticides has harmed soil and human health. Modern technology has also raised concerns about privacy, unemployment caused by automation, and the spread of misinformation through social media. These problems show that science is not good or bad in itself; it is the way society uses it that decides its consequences.

For this reason, society must guide science in a responsible direction. Governments should frame laws that promote the peaceful and sustainable use of science and technology. Scientists should be aware of the social and ethical effects of their work and should refuse to use their knowledge for harmful purposes. Ordinary citizens should be scientifically literate so that they can understand issues such as climate change, vaccination and digital privacy, and can demand accountability from their leaders. Education systems should encourage curiosity, critical thinking and research from an early age. Only when science and society move forward together with shared responsibility can the benefits of science reach everyone.

In conclusion, science and society are inseparable partners in human progress. Science provides the knowledge and tools, while society provides the purpose and direction. The challenge of our time is not to choose between science and society, but to build a wise relationship between them. If science is used with humanity, honesty and foresight, it can help solve the great problems of poverty, disease, hunger and environmental degradation. A society that respects science, and a science that serves society, together can create a better and more sustainable future for all.

1. Answer the following questions based on the passage given below:

a) Why is banning not a solution to every social problem? [2]

Because a ban only drives the banned activity underground instead of removing it. People who want to drink, gamble or use drugs will still find ways to do it, and the trade then passes into the hands of criminals. The problem is not removed; it is merely hidden, and it becomes harder to control, tax and regulate. Prohibition in America is the classic proof — drinking did not stop, but gangsterism and lawlessness grew. So the writer argues that society must be made aware of the harm and the habit discouraged, rather than simply outlawed.

b) How do Latin countries handle alcohol? [2]

In Latin countries alcohol is treated as a normal part of daily life rather than as a forbidden substance. Children are given wine with meals, so drinking is learnt in the family as a social custom and loses the glamour of a forbidden pleasure. Drunkenness is looked down upon as bad manners, not as a crime. As a result there is very little secret or excessive drinking, and the society does not need harsh laws to keep it in check.

c) Why does the writer oppose the idea of bringing new laws? [2]

Because new laws cannot remove the desire for a thing; they only punish the act after it has been done. The writer holds that the real cure lies in education, in changing people's attitude and habits, and in removing the conditions that create the problem. Laws multiply restrictions, create offences and give work to lawyers and police, but they do not touch the root cause. Hence he prefers social reform to legal prohibition.

2. Answer the following questions: [2×7.5=15]

a) In what ways is the power given by science superior to the power arising from faith and prayer? Discuss with reference to "God in the godless universe" by Bertrand Russell.

Russell's central argument is that science gives man real power over nature, while faith and prayer give only the feeling of power. The difference lies in the method and in the results.

First, science works through observation, experiment and verification. Its conclusions can be tested by anyone, anywhere, and are corrected when they are wrong. Faith and prayer, on the other hand, rest on authority, tradition and emotion; they cannot be tested, and their failures are explained away rather than admitted. A prayer for rain may or may not be followed by rain, but the same prayer is offered whether it rains or not — so nothing is ever learned.

Second, science delivers results that can be seen and used. Vaccination has wiped out smallpox, engineering has built bridges and dams, medicine has lengthened life. Russell points out that the believer's prayer for a sick child does not cure the child; the doctor's knowledge does. The power of science is therefore cumulative — each generation stands on the discoveries of the last — whereas faith remains static, repeating the same formulas century after generation.

Third, science is honest about its limits. It says "we do not know yet" and then goes on to find out. Faith claims certainty where there is none, and this false certainty has often been used to justify cruelty and persecution. Russell notes that the evils done in the name of religion — wars, inquisitions, the suppression of Galileo — show that faith's power is largely the power of one group over another, not power over nature.

Finally, Russell does not deny that faith and prayer give comfort. He admits that a person who prays may feel calmer and stronger. But this is a subjective feeling, not an objective gain; it changes the mind of the believer, not the course of events. Science, by contrast, changes the events themselves. In a godless universe, therefore, man must rely on his own knowledge and effort, and this is precisely why scientific power is superior — it is real, testable and effective, while the power of faith and prayer is imaginary.

b) Write a couple of paragraphs on benefits and safety risks of solar heat on the basis of your reading of H.A. Bethe's "The Cost of Solar Heat."

Bethe accepts that solar heat is a genuine and almost inexhaustible source of energy. Sunlight falls freely on the earth and needs no fuel, no mining and no transport. In warm and sunny regions it can heat water, dry crops, cook food and warm houses at very low running cost. It is clean, produces no smoke or ash, and does not pollute the air as coal and oil do. For a country like Nepal, with long hours of sunshine, solar heat can bring light and warmth to villages far from the electric grid. Bethe also notes that the total energy received from the sun is enormous compared with the energy man actually needs.

The difficulty, as Bethe explains, is that solar heat is dilute and intermittent. It arrives spread over a wide area and only during the day, so large collecting surfaces are needed to gather useful amounts. This makes the initial cost of solar plants high, and storage is required for cloudy days and for the night. The efficiency of collection is low, so the cost per unit of heat remains greater than that of conventional fuels in many places. There are also safety risks: concentrated sunlight can cause burns and eye damage, and large reflectors or panels must be strong enough to withstand storms. In short, solar heat is safe and clean in use, but its benefits depend on solving the problems of cost, storage and collection.

3.

a) Punctuation

i. This is his most recent novel, isn't it?

ii. When we started eating, the dog came and sat beside us.

iii. I lived in Namche until January 1990.

iv. She wore a red, blue and white sari.

v. Because of his arrogance, friendship is impossible.

b) Tense forms

i. He gave me as much advice as I needed.

ii. His writings were much better than I expected.

iii. He talks as if he were the boss of the company. (unreal comparison takes the subjunctive were)

iv. Whenever I go there, I remember my deceased mother.

v. He can write only if he has a pen.

4. Paragraph on "Man's treatment of man has not always been human."

Man's treatment of man has not always been human. History records slavery, in which people were bought, sold and worked without wages or freedom. Wars have been fought in which civilians were killed without mercy, and caste discrimination has denied ordinary people dignity and equal rights for centuries, as the Dalit communities of Nepal know well. Even today, child labour, human trafficking and domestic violence show that cruelty continues in new forms. Yet the same history shows the opposite side: reformers, doctors and ordinary people have worked to end slavery, to protect human rights and to treat every person with respect. The challenge for each generation is to make humanity in action as strong as humanity in word.

5. Technical essay: Use of Animals in Scientific Experimentation

Outline

1. Introduction: definition of animal experimentation.
2. Background: origin of the practice and the argument over it.
3. Discussion for: benefits to medicine and science.
4. Discussion against: cruelty, unreliability and alternatives.
5. Conclusion.

Introduction. Animal experimentation is the use of living animals, such as mice, rabbits, monkeys and dogs, in laboratory tests to study biology, to test the safety of drugs and chemicals, or to train researchers. It is one of the most debated practices in modern science.

Background. The practice is very old. Ancient Greek physicians dissected animals to learn anatomy, and in the nineteenth century Louis Pasteur used animals to develop vaccines against anthrax and rabies. In the twentieth century, tests on animals became compulsory before a new medicine could be given to humans. The ethical debate grew with the rise of the animal welfare movement.

Discussion (arguments for). Supporters argue that animal studies have saved millions of lives. Insulin for diabetes, vaccines for polio and measles, and surgical techniques were all developed using animals. Animals share many genes and organs with humans, so they can show whether a drug is toxic before humans take it. In a country like Nepal, vaccines used in national immunisation programmes were originally tested this way.

Discussion (arguments against). Critics argue that the animals suffer pain and fear, and that they have no choice. Results do not always carry over to humans, because a drug that is safe in a mouse may be harmful to a person. Alternatives now exist: cell cultures, computer models and human tissue "organs on chips". The "three Rs" (replace, reduce, refine) ask scientists to use animals only when there is no alternative, in the smallest number, and with the least suffering.

Conclusion. Animal experimentation has contributed greatly to human health, but it raises serious ethical questions. The sensible course is to use alternatives wherever possible, to permit animal tests only under strict ethical review, and to treat laboratory animals humanely.