Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word for each of the blanks.
 In recent years there have been many articles on air pollution in newspapers and magazines. Scientists all over the world have warned that our atmosphere is (1).....more and more contaminated, and that Man, through his carelessness, may run out of pure air to breathe.
Automobiles and industries mainly account (2).... air pollution in most cities. They pour into the air such gases as carbon monoxide, sulfur and nitrogen oxides, (3)...... are very harmful to humans. (4)......still, these gases, a series of chemical changes, turn into toxic acids. They fall down in “acid rains”, raising the acidity in the air, soil and water to dangerous levels and affecting not only tress but also fish and other wildlife. Many industrial countries in Europe and North America have suffered bad effects (5)......those “rains”.
Surely, Man faces no more urgent problem than that of saving his own survival. Scientists, social organizations and governments shout sit down together to solve the air pollution problem.
(3).........................

Are organically grown foods the best food choices? The advantages claimed for such foods over conventionally grown and marketed food products are now being debated. Advocates of organic foods - a term whose meaning varies greatly - frequently proclaim that such products are safer and more nutritious than others.
The growing interest of consumers in the safety and nutritional quality of the typical North American diet is a welcome development. However, much of this interest has been sparked by sweeping claims that the food supply is unsafe or inadequate in meeting nutritional needs.
Although most of these claims are not supported by scientific evidence, the preponderance of written material advancing such claims makes it difficult for the general public to separate fact from fiction. As a result, claims that eating a diet consisting entirely of organically grown foods prevents or cures disease or provides other benefits to health have become widely publicized and form the basis for folklore.
Almost daily the public is besieged by claims for “no-aging” diets, new vitamins, and other wonder foods. There are numerous unsubstantiated reports that natural vitamins are superior to synthetic ones, that fertilized eggs are nutritionally superior to unfertilized eggs, that untreated grains are better than fumigated grains, and the like.
One thing that most organically grown food products seem to have in common is that they cost more than conventionally grown foods. But in many cases consumers are misled if they believe organic foods can maintain health and provide better nutritional quality than conventionally grown foods. So there is real cause for concern if consumers, particularly those with limited incomes, distrust the regular food supply and buy only expensive organic foods instead.

The author implies that there is cause for concern if consumers with limited incomes buy organic foods instead of conventionally grown foods because ..........

Read the passage and choose the best answers:

Never say anything negative about past experiences, employers, or courses or professors. Always think of something positive about an experience and talk about that. You should also be __(1)__. If you are genuinely interested __(2)__ the job, let the interviewer know that.

One of the best ways to show you are keen on a job is to demonstrate that you have researched the organization prior to the interview. You can also __(3)__ interest by asking questions about the job, the organization, and its service and products. The best way to impress an employer is to ask questions that build your interview discussion. This shows you are interested and __(4)__ close attention to the interviewer. It is a good idea to prepare a few questions in advance, but an insightful comment based on your conversation can make an even stronger statement. At the __(5)__ of the interview, it is appropriate for you to ask when you may expect to hear from the employer.

__(2)__

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The nuclear family, consisting of a mother, father, and their children, may be more an American ideal than an American reality. Of course, the so-called traditional American family was always more varied than we had been led to believe, reflecting the very different racial, ethnic, class, and religious customs among different American groups.
The most recent government statistics reveal that only about one third of all current American families  fit the traditional mold and another third consists of married couples who either have no children or have none still living at home. Of the final one third, about 20 percent of the total number of American households are single people, usually women over sixty-five years of age. A small percentage, about 3 percent of the total, consists of unmarried people who choose to live together; and the rest, about 7 percent are single, usually divorced parents, with at least one child.
Today, these varied family types are typical, and therefore, normal. Apparently, many Americans are achieving supportive relationships in family forms other than the traditional one.

With what topic is the passage mainly concerned?

Quite different from storm surges are the giant sea waves called tsunamis, which derive their name from the Japanese expression for “high water in a harbor.” These waves are also referred to by the general public as tidal waves, although they have relatively little to do with tides.
Scientists often referred to them as seismic sea waves, far more appropriate in that they do result from undersea seismic activity.
Tsunamis are caused when the sea bottom suddenly moves, during an underwater earthquake or volcano for example, and the water above the moving earth is suddenly displaced. This sudden shift of water sets off a series of waves. These waves can travel great distances at speeds close to 700 kilometers per hour. In the open ocean, tsunamis have little noticeable amplitude, often no more than one or two meters. It is when they hit the shallow waters near the coast that they increase in height, possibly up to 40 meters.
Tsunamis often occur in the Pacific because the Pacific is an area of heavy seismic activity.
Two areas of the Pacific well accustomed to the threat of tsunamis are Japan and Hawaii. Because the seismic activity that causes tsunamis in Japan often occurs on the ocean bottom quite close to the islands, the tsunamis that hit Japan often come with little warning and can, therefore, prove disastrous. Most of the tsunamis that hit the Hawaiian Islands, however, originate thousands of miles away near the coast of Alaska, so these tsunamis have a much greater distance to travel and the inhabitants of Hawaii generally have time for warning of their imminent arrival.
Tsunamis are certainly not limited to Japan and Hawaii. In 1755, Europe experienced a calamitous tsunami, when movement along the fault lines near the Azores caused a massive tsunami to sweep onto the Portuguese coast and flood the heavily populated area around Lisbon. The greatest tsunami on record occurred on the other side of the world in 1883 when the Krakatoa volcano underwent a massive explosion, sending waves more than 30 meters high onto nearby Indonesian islands; the tsunami from this volcano actually traveled around the world and was witnessed as far away as the English Channel.

It can be inferred from the passage that tsunamis ...............

Choose the word or phrase that best fits each space in the following passage

THE FIRST WOMAN SCIENTIST

Hypatia was born in Alexandria, in Egypt, in 370 A.D. For many centuries, she was the only woman (1) ___________ to have a place in the history books. Hypatia's father was the director of Alexandria University, and he (2) ______________ sure his daughter had the best education available. This was unusual, as most women then had few opportunities to study.

After studying in Athens and Rome, Hypatia returned to Alexandria (3)_______ she began teaching  mathematics. She soon became famous for her knowledge of new ideas.

There are no copies of her books, but it is said that she wrote several important mathematical works. Hypatia was also interested in technology and (4)___________ several scientific tools to help with her work.

At the time, many rulers were afraid of science, and something connected with it was (5)_________ danger. One day in March 415, Hypatia was attacked in the street and killed.

During the 20th century, Hypatia was seen as a symbol of the women's rights movement, a precursor to the feminist movement. Since the late 20th century, Hypatia's death has at times been associated with the destruction of the Library of Alexandria, although historically the library ceased to exist in Hypati.

(3) _________

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In this modern world where closed-circuit television (CCTV) cameras are everywhere and smartphones in every pocket, the routine filming of everyday life is becoming pervasive. A number of countries are rolling out body cams for police officers; other public-facing agencies such as schools, councils and hospitals are also experimenting with cameras for their employees. Private citizens are getting in on the act too: cyclists increasingly wear headcams as a deterrent to aggressive drivers. As camera technology gets smaller and cheaper, it isn't hard to envisage a future where we're all filming everything all the time, in every direction.
Would that be a good thing? There are some obvious potential upsides. If people know they are on camera, especially when at work or using public services, they are surely less likely to misbehave. The available evidence suggests that it discourages behaviours such as vandalism. Another upside is that it would be harder to get away with crimes or to evade blame for accidents.
But a world on camera could have subtle negative effects. The deluge of data we pour into the hands of Google, Facebook and others has already proved a mixed blessing. Those companies would no doubt be willing to upload and curate our body-cam data for free, but at what cost to privacy and freedom of choice?
Body-cam data could also create a legal minefield. Disputes over the veracity and interpretation of police footage have already surfaced. Eventually, events not caught on camera could be treated as if they didn't happen. Alternatively, footage could be faked or doctored to dodge blame or incriminate others.
Of course, there's always the argument that if you're not doing anything wrong, you have nothing to fear. But most people have done something embarrassing, or even illegal, that they regret and would prefer they hadn't been caught on film. People already censor their social media feeds – or avoid doing anything incriminating in public – for fear of damaging their reputation. Would ubiquitous body cams have a further chilling effect on our freedom?
The always-on-camera world could even threaten some of the attributes that make us human. We are natural gossips and backbiters, and while those might not be desirable behaviours, they oil the wheels of our social interactions. Once people assume they are being filmed, they are likely to clam up.
The argument in relation to body-cam ownership is a bit like that for guns: once you go past a critical threshold, almost everyone will feel they need one as an insurance policy. We are nowhere near that point yet – but we should think hard about whether we really want to say "lights, body cam, action." 

What does the author imply in paragraph 3?

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks .
A recent (1)....... of a language learning magazine has consulted a number of experts in the field of second language acquisition. Their advice may prove invaluable for those considering a language course. One suggestion is that you access whether you are likely to be successful (2)........ learning a language. Did you enjoy studying language at school, for example? Do you have enough time to learn a language ? The major cost will be your own time and effort. Therefore, you must make sure that course on  offer  leads  to  a  recognized  qualification.  Also,  be  realistic  in your (3).......... If you don’t set achievable aims, you are more likely to give up. Don’t be deceived into thinking that the most expensive courses are the best. Shop around to get the best possible value for money. You should also bear in your mind that the quicker you learn a language, the more quickly you forget it. Sandra Miller, a French teacher, tried to teach herself German by enrolling on a crash course. Already fluent in four languages and with a sound knowledge of teaching methodology her chances of (4)........ progress were high. Three years on she remembers very little. She feels her biggest mistake was not to follow up her first experience.  "I  think  the  teacher’s  role  is  important.  It's  so  nice  to  have  somebody  give  you  a/an (5) ........... ”.
(4)................................
 

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On the tiny island of Flores, east of Bali and midway between Asia and Australia, the scientists have discovered the remains of a small, hobbit-like species of humans. These people grew no larger than the modern three-year-old child. They lived about 18,000 years ago and are completely different species of human.
This discovery has taught scientists a lot about the human species. This remarkable discovery shows that the human species is more varied and flexible in its ability to adapt than previously thought. These hobbit-like people join a short list of other type of humans that lived with modern humans.
The researchers believe that these hobbits evolved from a normal size, human population that reached Flores around 840,000 years ago. One likely explanation is that, over thousands of years, the species became smaller because the environmental conditions favored a smaller body size. The dwarfing of mammals on islands occurs frequently. Islands limit food supply and predators and species compete for the same environmental space. Survival would depend on minimizing energy requirements.a

Which of the following is true of the newly discovered species?

The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life. They are fantastically diverse, but three major groups may be identified on the basis of their motility. The Mastigophora have one or more long tails, which they use to project themselves forward. The Ciliata, which use the same basic means for locomotion as the Mastigophora, have a larger number of short tails. The Sarcodina, which include amoebae, float or row themselves about on their crusted bodies.
In addition to their form of movement, several other features discriminate among the three groups of protozoans. For example, at least two nuclei per cell have been identified in the Ciliata, usually a large nucleus that regulates growth but decomposes during reproduction, and a smaller one that contains the genetic code necessary to generate the large nucleus.
Protozoans are considered animals because, unlike pigmented plants to which some protozoans are otherwise almost identical, they do not live on simple organic compounds. Their cell demonstrates all of the major characteristics of the cells of higher animals.
Many species of protozoans collect into colonies, physically connected to each other and responding uniformly to outside stimulate. Current research into this phenomenon, along with investigations carried out with advanced microscopes may necessitate a redefinition of what constitutes protozoans, even calling into question the basic premise that they have only one cell. Nevertheless, with the current data available, almost 40,000 species of protozoans have been identified. No doubt, as the technology improves our methods of observation, better models of classification will be proposed.

The word “they” in paragraph 3 refers to...............

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We live in a world of tired, sleep deprived people. In his book Counting Sheep, Paul Martin - a behavioural biologist - describes a society which is just too busy to sleep and which does not givesleeping the importance it deserves.
Modern society has invented reasons not to sleep. We are now a 24/7 society where shops and services must be available all hours. We spend longer hours at work than we used to, and more time getting to work. Mobile phones and email allow us to stay in touch round the clock and late-night TV and the Internet tempt us away from our beds. When we need more time for work or pleasure, the easy solution is to sleep less. The average adult sleeps only 6.2 hours a night during the week, whereas research shows that most people need eight or even eight and a half hours' sleep to feel at their best.
Nowadays, many people have got used to sleeping less than they need and they live in an almost permanent state of 'sleep debt'.
Until the invention of the electric light in 1879 our daily cycle of sleep used to depend on the hours of daylight. People would get up with the sun and go to bed at nightfall. But nowadays our hours of sleep are mainly determined by our working hours (or our social life) and most people are woken up artificially by an alarm clock. During the day caffeine, the world's most popular drug, helps to keep us awake. 75% of the world's population habitually consume caffeine, whichup to a point masks the symptoms of sleep deprivation.
What does a chronic lack of sleep do to us? As well as making us irritable and unhappy as humans, it also reduces our motivation and ability to work. This has serious implications for society in general.
Doctors, for example, are often chronically sleep deprived, especially when they are on 'night call', and may get less than three hours' sleep. Lack of sleep can seriously impair their mood, judgment, and ability to take decisions. Tired engineers, in the early hours of the morning, made a series of mistakes with catastrophicresults. On our roads and motorways lack of sleep kills thousands of people every year. Tests show that a tired driver can be just as dangerous as a drunken driver. However, driving when drunk is against the law but driving when exhausted isn't. As Paul Martin says, it is very ironic that we admire people who function on very little sleep instead of criticizing them for being irresponsible. Our world would be a much safer, happier place if everyone, whatever their job, slept eight hours a night.

According to the third paragraph, which of the following statements is NOT TRUE?

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In the exploration of the linguistic life cycle, it is apparent that it is much more difficult to learn a second language in adulthood than a first language in childhood. Most adults never completely master foreign language, especially in phonology - hence the ubiquitous foreign accent. Their development often "fossilizes" into permanent error patterns that no teaching or correction can do. Of course, there are great individual differences, which depend on effort, attitudes, amount of exposure, quality of teaching and plain talent, but there seems to be a cap for the best adults in the best circumstances.
Many explanations have been advanced for children's superiority: they exploit Motherless (the simplified, repetitive conversation between parents and children), make errors oneself- consciously, are more motivated to communicate, like to conform, are not set in their ways, and have no first language to interfere. But some of these accounts are unlikely, based on what is known about how language acquisition works. Recent evidence is calling these social and motivation explanations into doubt. Holding every other factor constant, a key factor stands out: sheer age.
Systematic evidence comes from the psychologist Elisa Newport and her colleagues. They tested Korean and Chinese-born students at the University of Illinois who had spent at least ten years in the United States. The immigrants were given a list of 276 simple English sentences, half of them containing some grammatical errors. The immigrants who came to the United States between the ages of 3 and 7 performed identically to American bom students. Those who arrived between the ages of 8 and 15 did worse the later they arrived, and those who arrived between 17 and 39 did the worst of all, and showed huge variability unrelated to their age of arrival.

It can be inferred from the passage that "phonology" is the study of the.................. of a language.

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Perhaps better known than the Cullinan Diamond is the Hope Diamond, a valuable and blue gem with a background of more than 300 years as a world traveler.The 112-carat blue stone later became the Hope Diamond was mined in India sometime before the middle of the seventeenth century and was first known to be owned by Shah Jahan, who built the Taj Mahal in memory of his beloved wife. From India, the celebrated blue stone has changed hands often, moving from location to location in distant corners of the world.
In the middle of the seventeenth century, a trader from France named Jean Baptiste Tavernier acquired the large blue diamond, which was rumored to have been illegally removed from a temple Tavemier returned to France with the big blue gem, where the stone was purchased by the Sun King Louis XIV. Louis XIV had it cut down from 112 to 67 carats to make its shape symmetrical and to maximize its sparkle. The newly cut diamond, still huge by any standards, was passed down through the royal family of France, until it arrived in the hands of Louis XVI and Marie Antoinette.
During the French Revolution, Louis XVI and his wife met their fate on the guillotine in 1793, and the big blue diamond disappeared from public sight.
The diamond somehow managed to get from France to England, where banker Henry Hope purchased it from a gem dealer early in the nineteenth century. The huge blue stone was cut into a 45.5-carat oval, and at this point it took on the name by which it is known today. The diamond stayed in the Hope family for around a century, when deep indebtedness brought on by a serious gambling habit on the part of one of Henry Hope's heirs forced the sale of the diamond.
From England, the Hope Diamond may have made its way into the hands of the Sultan of Turkey; whatever route it took to get there, it eventually went on to the United States when American Evelyn Walsh McLean purchased it in 1911. Mrs.
McLean certainly enjoyed showing the diamond off guests in her home were sometimes astounded to notice the huge stone embellishing the neck of Mrs. McLean’s Great Dane as the huge pet trotted around the grounds of her Washington, D.C. home. The Hope Diamond later became the property of jeweler Harry Winston, who presented the stunning 45.5- carat piece to the Smithsonian in 1958. The Hope Diamond is now taking a well-earned rest following its rigorous travel itinerary and is on display at the Smithsonian Institution in Washington, D.C., where it has been since 1958.

Which country is NOT mentioned in the passage as a place where the Hope Diamond spent some time?

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Most volcanoes are found along an imaginary belt, called the Ring of Fire, that encircles the Pacific Ocean. However, volcanic activity takes place in many far-flung regions of the world such as Hawaii, Iceland, Europe, and even the floor of the earth’s oceans. The leading theory as to why volcanic activity, as well as earthquakes, takes place when and where it does is called the theory of “plate tectonics”. The theory holds that the outer shell of the earth is divided into many different rigid sections of rock, called plates. These plates are not static, they are in continuous motion over a layer of partly melted rock. While their movement may appear insignificant, at only several inches per year, it is not. Indeed, the collisions between plates caused by this almost imperceptible movement can have catastrophic consequences. Volcanic activity and earthquakes are concentrated near the boundaries of these giant, moving plates.
The majority of volcanoes are formed at te point where two plates collide. One of the plates is forced underneath the other. As the plate sinks, the earth’s heat and the friction of the movement cause a portion of the sinking plate to melt. This melted portion of plate is called magma, and when it reaches the earth’s surface it becomes a volcano. Volcanoes can also be created when two plates begin to diverge. Then, magma from below the earth’s crust moves up to fill the void between the two plates. Large quantities of lava spill out from the void. Volcanoes of this type usually are found not on land, but on the ocean floor. In extreme instances this can lead to the formation of gigantic, sunken mountain ranges like Mid-Atlantic Ridge that spans nearly the entire length of the Atlantic Ocean. The theory of plate tectonics also explains why some volcanic activity takes place so far from any known plate boundaries. Basically, these volcanoes are the result of huge column of magma, or plumes, that rise up and break through the surface of the earth.

The Ring of Fire is     .

Choose the best answer: 
We are all slowly (1) __________  the earth. The seas and rivers are too dirty to swim in.
There is so much smoke in the air that it is unhealthy to live in many of the world’s cities. In one well-
known city, for example, poisonous gases (2) __________ cars pollute the air so much that traffic
policemen have to wear oxygen masks. We have cut down (3) __________ trees that there are now
vast areas of wasteland all over the world. As a result, farmers in parts of Africa cannot grow enough
(4) __________. In certain countries in Asia, there is too little rice. Moreover, we do not take care of
the countryside.
Wild animals are quickly disappearing. For instance, tigers are rare in India now because we
have killed too many of them. However, it isn’t enough simply to talk about the problem. We must act
now before it is too late to do (5) __________ about it. Join us now. Save the Earth!
4.

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In the late 1960’s, many people in North America turned their attention to environmental problems and new steel-and-glass skyscrapers were widely criticized. Ecologists pointed out that a cluster of tall buildings in a city often overburdens public transportation and parking lot capacities.
Skyscrapers are also lavish consumers, and waster, of electric power. In one recent year, the addition of 17 million square feet of skyscraper office space in New York City raised the peak daily demand for electricity by 120,-000 kilowatts- enough to supply the entire city of Albany, New York, for a day.
Glass-walled skyscrapers can be especially wasteful. The heat loss (or gain) through a wall of half-inch plate glass is more than ten times that through a typical masonry wall filled with insulation board. To lessen the strain on heating and air- conditioning equipment, builders of skyscrapers have begun to use double glazed panels of glass, and reflective glasses coated with silver or gold mirror films that reduce glare as well as heat gain. However, mirror-walled skyscrapers raise the temperature of the surrounding air and affect neighboring buildings.
Skyscrapers put a severe strain on a city’s sanitation facilities, too. If fully occupied, the two World Trade Center towers in New York City would alone generate 2.25 million gallons of raw sewage each year-as much as a city the size of Stamford, Connecticut, which has a population of more than 109,000.
Skyscrapers also interfere with television reception, block bird flyways, and obstruct air traffic. In Boston, in the late 1960’s some people even feared that shadows from skyscrapers would kill the grass on Boston Common.
Still, people continue to build skyscrapers for all the reasons that they have always built them – personal ambition, civic pride, and the desire of owners to have the largest possible amount of rentable space.

According to the passage, all of the following are mentioned as reasons for building skyscrapers EXCEPT

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks.
          Keeping the World in Our Pockets
Faster processors and advances in memory technology have made today’s smartphones much more powerful than a lot of computers from just a decade ago. With wireless technology, people can surf the Internet, play online games, send e-mail, and do (1)............ all the things they once could only do on a computer. (2)......... , they have the power to do things constantly at their fingertips.
Many people (3)....... that while smartphones are powerful tools, they are making people reliant on them. Why would a person need to learn to read a map when he can get directions to anywhere by simply asking his phone a question? Who needs to learn maths when you have immense calculating power in your pocket at all times? What (4).........is there to memorise facts about history, art, or geography when that information is readily available from a portable Internet interface?
There are just some of the questions being asked and answered as smartphone usage continues to spread. Like any technology, smartphones have their advantages, but they do have disadvantages as well that we must (5).......... an eye on.
(1)............................

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Genetic modification of foods is not a new practice. It has been practiced for thousands of years under the name of "selective breeding". Animals and plants were chosen because they had traits that humans found useful. Some animals were larger and stronger than others, or they yielded more food, or they had some other trait that humans valued. Therefore, they were bred because of those traits. Individuals with those traits were brought together and allowed to breed in the hope that their offspring would have the same traits in greater measure.
Much the same thing was done with plants. To produce bigger or sweeter fruit, or grow more grain per unit of land, strains of plants were combined and recombined to produce hybrids, or crossbreeds that had the desired traits in the right combinations. All the while, however, biologists wondered: is there a more direct and versatile way to change the traits of plants and animals? Could we rewrite, so to speak, the heredity of organisms to make them serve our needs better?
In the 20th century, genetic modification made such changes possible at last. Now, it was possible to alter the genetic code without using the slow and uncertain process of selective breeding. It even became possible to blend plants and animals genetically: to insert animal genes into plants, for example, in order to give the plants a certain trait they ordinarily would lack, such as resistance to freezing. The result was a tremendous potential to change the very nature of biology.

The word "blend" in paragraph 3 mostly means     .

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George Washington Carver showed that plant life was more than just food for animals and humans. Carver’s first step was to analyze plant parts to find out what they were made of. He then combined these simpler isolated substances with other substances to create new products.
The branch of chemistry that studies and finds ways to use raw materials from farm products to make industrial products is called chemurgy. Carver was one of the first and greatest chemurgists of all time. Today the science of chemurgy is better known as the science of synthetics. Each day people depend on and use synthetic materials made from raw materials. All his life Carver battled against the disposal of waste materials and warned of the growing need to develop substitutes for the natural substances being used up by humans.
Carver never cared about getting credit for the new products he created. He never tried to patent his discoveries or get wealthy from them. He turned down many offers to leave Tuskegee Institute to become a rich scientist in private industry. Thomas Edison, inventor of the electric light, offered him a laboratory in Detroit to carry out food research. When the United States government made him a collaborator in the Mycology and Plant Disease Survey of the Department of Agriculture, he accepted the position with the understanding that he wouldn’t have to leave Tuskegee. As an authority on plant diseases – especially of the fungus variety – Carver sent hundreds of specimens to the United States Department of Agriculture. At the peak of his career, Carver’s fame and influence were known on every continent.

According to the passage, chemurgical can be defined as the

No educational medium better as means of spatial communication than the atlas. Atlases deal with such invaluable information as population distribution and density. One of the best, Pennycooke's World Atlas, has been widely accepted as a standard owing to the quality of its maps and photographs, which not only show various settlements but also portray them in a variety of scales. In fact, the very first map in the atlas is a cleverly designed population cartogram that projects the size of each country if geographical size were proportional to population. Following the proportional layout, a sequence of smaller maps shows the world’s population density, each country’s birth and death rates, population increase or decrease, industrialization, urbanization, gross national product in terms of per capita income, the quality of medical care, literacy, and language. To give readers a perspective on how their own country fits in with the global view, additional projections depict the world's patterns in nutrition, calorie and protein consumption, health care, number of physicians per unit of population, and life expectancy by region. Population density maps on a subcontinental scale, as well as political maps. Convey the diverse demographic phenomena of the world in a broad array of scales.

What is the main topic of the passage?