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 give sleeping 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 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, which up 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 got 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 catastrophic results. 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

Which of the following would the writer of the passage approve of?

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

   Many flowering plants woo insect pollinators and gently direct them to their most fertile blossoms by changing the color of individual flowers from day to day. Through color cues, the plant signals to the insect that it would be better off visiting one flower on its bush than another. The particular hue tells the pollinator that the flower is full of far more pollen than are neighboring blooms. That nectar-rich flower also happens to be fertile and ready to disperse its pollen or to receive pollen the insect has picked up from another flower. Plants do not have to spend precious resources maintaining reservoirs of nectar in all their flowers. Thus, the color-coded communication system benefits both plants and insects.

   For example, on the lantana plant, a flower starts out on the first day as yellow, when it is rich with pollen and nectar. Influenced by an as-yet-unidentified environmental signal, the flower changes color by triggering the production of the pigment anthromyacin. It turns orange on the second day and red on the third. By the third day, it has no pollen to offer insects and is no longer fertile. On any given lantana bush, only 10 to 15 per cent of the blossoms are likely to be yellow and fertile. But in tests measuring the responsiveness of butterflies, it was discovered that the insects visited the yellow flowers at least 100 times more than would be expected from haphazard visitation. Experiments with paper flowers and painted flowers demonstrated that the butterflies were responding to color cues rather than, say, the scent of the nectar.

   In other types of plants, blossoms change from white to red, others from yellow to red, and so on. These color changes have been observed in some 74 families of plants.

Which of the following describes the sequence of color changes that lantana blossom undergo?

Learning means acquiring knowledge or developing the ability to perform new behaviors. It is common to think of learning as something that takes place in school, but much of human learning occurs outside the classroom, and people continue to learn throughout their lives.
Even before they enter school, young children learn to walk, to talk, and to use their hands to manipulate toys, food, and other objects. They use all of their senses to learn about the sights, sounds, tastes, and smells in their environments. They learn how to interact with their parents, siblings, friends, and other people important to their world. When they enter school, children learn basic academic subjects such as reading, writing, and mathematics. They also continue to learn a great deal outside the classroom. They learn which behaviors are likely to be rewarded and which are likely to be punished. They learn social skills for interacting with other children. After they finish school, people must learn to adapt to the many major changes that affect their lives, such as getting married, raising children, and finding and keeping a job.
Because learning continues throughout our lives and affects almost everything we do, the study of learning is important in many different fields. Teachers need to understand the best ways to educate children. Psychologists, social workers, criminologists, and other human- service workers need to understand how certain experiences change people's behaviors.
Employers, politicians, and advertisers make use of the principles of teaming to influence the behavior of workers, voters, and consumers.
Learning is closely related to memory, which is the storage of information in the brain.
Psychologists who study memory are interested in how the brain stores knowledge, where this storage takes place, and how the brain later retrieves knowledge when we need it. In contrast, psychologists who study learning are more interested in behavior and how behavior changes as a result of a person's experiences.
There are many forms of learning, ranging from simple to complex. Simple forms of learning involve a single stimulus. A stimulus is anything perceptible to the senses, such as a sight, sound, smell, touch, or taste. In a form of learning known as classical conditioning, people learn to associate two stimuli that occur in sequence, such as lightning followed by thunder. In operant conditioning, people learn by forming an association between a behavior and its consequences (reward or punishment). People and animals can also learn by observation - that is, by watching others perform behaviors. More complex forms of learning include learning languages, concepts, and motor skills

According to the passage, the study of learning is important in many fields due to     :

Choose the best answer.

_______ for my train the morning, I met an old school friend

Some animal behaviorists argue that certain animals can remember past events, anticipate future ones, make plans and choices, and coordinate activities within a group. These scientists, however, are cautious about the extent to which animals can be credited with conscious   processing.
Explanations of animal behavior that leave out any sort of consciousness at all and ascribe actions entirely to instinct leave many questions unanswered. One example of such unexplained behavior: Honeybees communicate the sources of nectar to one another by doing a dance in a figure-eight pattern. The orientation of the dance conveys the position of the food relative to the sun's position in the sky, and the speed of the dance tells how  far  the food source is from  the  hive. Most researchers assume that the ability to perform and  encode the dance is innate and  shows no special intelligence. But in one study, when experimenters kept changing the site of the food source, each time moving the food 25 percent father from the previous site, foraging honeybees began to anticipate where the food source would appear next. When the researchers arrived at the new location, they would find the bees circling the spot, waiting for their food. No one has yet explained how bees, whose brains weigh four ten-thousandths of an  ounce,  could  have inferred the location of the new  site.
Other behaviors that may indicate some cognition include tool use. Many animals, like the otter who uses a stone to crack mussel shells, are capable of using objects in the natural environment as rudimentary tools. One researcher has found that mother  chimpanzees  occasionally show their young how to use tools to open hard nuts. In one study, chimpanzees compared two pairs of food wells containing chocolate chips. One pair might contain, say, five chips and three chips, the other four chips and three chips. Allowed to choose which pair they wanted, the  chimpanzees  almost always chose the one with the higher total, showing some sort  of summing ability. Other chimpanzees have learned to use numerals to label quantities of items and do simple sums.

The phrase "the one" refer  to the..................

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions.

Born on June 30, 1985 in Baltimore, Maryland, to Fred and Debbie Phelps, the youngest of three children, Michael Phelps and his sisters grew up in the neighbourhood of Rodger Forge. His father, Fred, a former all-rounded athlete, was a state trooper and his mother Debbie was a middle-school principal. When Phelps's parents divorced in 1994, he and his siblings lived with their mother, with whom Michael grew very close. Even at the age of 7, Phelps was still a little scared to put his head under water, so his instructors allowed him to float around on his back. Not surprisingly, despite the fact that later he is very good at butterfly swimming, the first stroke he mastered was not the easily-practised breaststroke but the backstroke.

At the age of 15, Phelps became the youngest American male swimmer to compete at an Olympic Games in 68 years. While he didn't win any medals at the 2000 Summer Olympics in Sydney, Australia, he would soon become a major force in competitive swimming.

In the spring of 2001, Phelps set the world record in the 200-meter butterfly, becoming the youngest male swimmer in history at the age of 15 years and 9 months. At the 2001 World Championships in Japan, he then broke his own record with a time of 1:54:58, earning his first international medal. In 2002, Phelps continued to establish several records including the 100-meter butterfly and the 200-meter individual medley. The following year, at the same event, he broke his own world record in the 400-meter individual medley with a time of 4:09.09.

After the London Olympics in 2012, Phelps announced he was retiring from his sport. However, at the 2016 Olympic Games, he came out of retirement and returned to professional competition. This was also the event in which he won one silver and five gold medals, becoming the oldest individual gold medalist in Olympic swimming history, as well as the first swimmer to win four consecutive golds in the same event, the 200 meter individual medley.

The first style of swimming Phelps was good at is ____.

Although they are an inexpensive supplier of vitamins, minerals, and high-quality protein, eggs also contain  a high  level of blood cholesterol, one of the major causes of heart diseases. One egg   yolk, in fact, contains a little more than two-thirds of the suggested daily cholesterol limit. This knowledge has caused egg sales to plummet in recent years, which in turn has brought about the development of several alternatives to eating regular eggs. One alternative is to eat substitute eggs. These egg substitutes are not really eggs, but they look somewhat like eggs when  they are  cooked. They have the advantage of having low cholesterol rates, and they can be  scrambled  or  used  in baking. One disadvantage, however, is that they are not good for frying, poaching,  or boiling.  A second alternative to regular eggs is a new type of egg, sometimes called 'designer' eggs. These eggs  are produced by hens that are fed low-fat diets consisting of Ingredients such as canola oil, flax, and rice bran. In spite of their diets, however, these hens produce eggs that contain the same amount of cholesterol as regular eggs. Yet, the producers of these eggs claim that eating their eggs will not raise the blood cholesterol in  humans.
Egg producers  claim  that their product has been  portrayed unfairly. They cite scientific studies  to back up their claim. And, in fact, studies on the relationship between eggs and human cholesterol levels have brought mixed results. It may be that it is not the type of egg that is the main determinant   of cholesterol but the person who is eating the eggs. Some people may be  more  sensitive  to  cholesterol derived from food than other people. In fact, there is evidence that certain dietary fats stimulate the body's production of blood cholesterol. Consequently, while it still makes sense to limit one's intake of eggs, even designer eggs, it seems that doing this without regulating dietary fat will probably not help reduce the blood cholesterol  level.

Which of the following could best replace the word   'somewhat'?

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:
Humans are bringing about another global-scale change in the atmosphere: the increase in what are called greenhouse gases. Like glass in a greenhouse, these gases admit the Sun's light but tend to reflect back downward the heat that is radiated from the ground below, trapping heat in the Earth's atmosphere. This process is known as the greenhouse effect. Carbon dioxide is the most significant of these gases – there is 25 percent more carbon dioxide in the atmosphere today than there was a century ago, the result of our burning coal and fuels derived from oil. Methane, nitrous oxide, and CFCs are greenhouse gases as well.
Scientists predict that increases in these gases in the atmosphere will make the Earth a warmer place. They expect a global rise in average temperature somewhere between 1.0 and 3.5 degrees Celsius in the next century. Average temperatures have in fact been rising and the years from 1987 to 1997 were the warmest years on record. Some scientists are reluctant to say that global warming has actually begun because climate naturally varies from year to year and decade to decade, and it takes many years of records to be sure of a fundamental change. There is little disagreement, though, that global warming is looming.
Global warming will have different effects in different regions. A warmed world is expected to have more extreme weather, with more rain during wet periods, longer droughts, and more powerful storms. Although the effects of future climate changes are unknown, some predict that exaggerated weather conditions may translate into better agricultural yields in areas such as the western United States, where temperature and rainfall are expected to increase, while dramatic decreases in rainfall may lead to severe droughts and plunging agricultural yields in parts of Africa, for example.
Warmer temperatures are expected to partially melt the polar ice caps, leading to a projected sea level rise of 50 centimeters by the year 2050. A sea level rise of this magnitude would flood coastal cities, force people to abandon low-lying islands, and completely inundate coastal wetlands. Diseases like malaria, which at present are primarily found in the tropics, may become more common in the regions of the globe between the tropics and the polar regions, called the temperate zones. For many of the world's plant species, and for animal species that are not easily able to shift their territories as their habitat grows warmer, climate change may bring extinction.

The word "looming" in paragraph 2 probably means .....................

Although they are an inexpensive supplier of vitamins, minerals, and high-quality protein, eggs also contain  a high  level of blood cholesterol, one of the major causes of heart diseases. One egg   yolk, in fact, contains a little more than two-thirds of the suggested daily cholesterol limit. This knowledge has caused egg sales to plummet in recent years, which in turn has brought about the development of several alternatives to eating regular eggs. One alternative is to eat substitute eggs. These egg substitutes are not really eggs, but they look somewhat like eggs when  they are  cooked. They have the advantage of having low cholesterol rates, and they can be  scrambled  or  used  in baking. One disadvantage, however, is that they are not good for frying, poaching,  or boiling.  A second alternative to regular eggs is a new type of egg, sometimes called 'designer' eggs. These eggs  are produced by hens that are fed low-fat diets consisting of Ingredients such as canola oil, flax, and rice bran. In spite of their diets, however, these hens produce eggs that contain the same amount of cholesterol as regular eggs. Yet, the producers of these eggs claim that eating their eggs will not raise the blood cholesterol in  humans.
Egg producers  claim  that their product has been  portrayed unfairly. They cite scientific studies  to back up their claim. And, in fact, studies on the relationship between eggs and human cholesterol levels have brought mixed results. It may be that it is not the type of egg that is the main determinant   of cholesterol but the person who is eating the eggs. Some people may be  more  sensitive  to  cholesterol derived from food than other people. In fact, there is evidence that certain dietary fats stimulate the body's production of blood cholesterol. Consequently, while it still makes sense to limit one's intake of eggs, even designer eggs, it seems that doing this without regulating dietary fat will probably not help reduce the blood cholesterol  level.

What has been the cause for changes in the sale of eggs?

Read the passage below and choose the best answer (A, B, C or D ) to each question.

Higher education, also called tertiary, third stage or post secondary education, is the non-compulsory educational level following the completion of a school providing a secondary education, such as a high school, secondary school. Tertiary education is normally taken to include undergraduate and postgraduate education, as well as vocational education and training. Colleges and universities are the main institutions that provide tertiary institutions. Tertiary education generally results in the receipt of certificates, diplomas, or academic degrees.

Higher education includes teaching, research and social services activities of universities, and within the realm of teaching, it includes both the undergraduate level and the graduate level. Higher education in that country generally involves work towards a degree-level or foundation degree qualification. It is therefore very important to national economies, both as a significant industry in its own right, and as a source of trained and educated personnel for the rest of the economy.

Where can we find tertiary education? 

Choose the letter A, B, C or D to answer these following questions:
The ASEAN Declaration states that the aims and purposes of the Association are: (1) to accelerate the economic growth, social progress and cultural development in the region through joint endeavors in the spirit of equality and partnership in order to strengthen the foundation for a prosperous and peaceful community of Southeast Asian nations, and (2) to promote regional peace and stability through abiding respect for justice and the rule of law in the relationship among countries in the region and adherence to the principles of the United Nations Charter. In 1995, the ASEAN Heads of State and Government re-affirmed that “Cooperative peace and shared prosperity shall be the fundamental goals of ASEAN.”
TAC stated that ASEAN political and security dialogue and cooperation should aim to promote regional peace and stability by enhancing regional resilience. Regional resilience shall be achieved by cooperating in all fields based on the principles of self-confidence, self-reliance, mutual respect, cooperation, and solidarity, which shall constitute the foundation for a strong and viable community of nations in Southeast Asia.
Although ASEAN States cooperate mainly on economic and social issues, the organization has a security function, with a long-discussed program for confidence-building measures and for establishing a nuclear-weapon-free zone in Southeast Asia, with the objective of implementing ASEAN’s 1971 Declaration on a Zone of Peace, Freedom and Neutrality (ZOPFAN), and a Southeast Asia Nuclear Weapon-Free Zone (SEANWFZ), which would be a component of ZOPFAN

When was the ASEAN’s Declaration on a Zone of Peace adopted?

Read the passage carefully and choose the correct answer

On 8 August 1967, five leaders - the Foreign Ministers of Indonesia, Malaysia, the Philippines, Singapore and Thailand- sat down together in the main hall of the Department of Foreign Affairs building in Bangkok, Thailand and signed a document. By virtue of that document, the Association of Southeast Asian Nations (ASEAN) was born. The five Foreign Ministers who signed it have been considered as the founders of probably the most successful intergovernmental organization in the developing world today. The document that they signed would be known as the ASEAN Declaration.

It is a short, simply-worded document containing just five articles. It declares the establishment of an Association for Regional Cooperation among the Countries of Southeast Asia to be known as the Association of Southeast Asian Nations (ASEAN) and spells out the aims and purposes of that Association. These aims and purposes are about the cooperation in economy, society, culture, techniques, education and other fields, and in the promotion of regional peace and stability through abiding respect for justice and the principles of the United Nations Charter. It stipulates that the Association will be open for participation by all States in the Southeast Asian region subscribing to its aims, principles and purposes. It proclaims ASEAN as representing the collective will of the nations of Southeast Asia to bind themselves together in friendship and cooperation and, through joint efforts and sacrifices, secure for their peoples and for posterity the blessings of peace, freedom and prosperity. The goal of ASEAN, then, is to create, not to destroy.

The original ASEAN logo presented five brown sheaves of rice stalks, one for each founding member. Beneath the sheaves is the legend "ASEAN" in blue. These are set on a field of yellow encircled by a blue border. Brown stands for strength and stability, yellow for prosperity and blue for the spirit of cordiality in which ASEAN affairs are conducted. When ASEAN celebrated its 30^th Anniversary in 1997, the sheaves on the logo had increased to ten -representing all ten countries of Southeast Asia and reflecting the colors of the flags of all of them. In a very real sense, ASEAN and Southeast Asia will be one and the same, just as the founders had envisioned.

The pronoun "it" in the first paragraph refers to ________.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

   Traditional methods of teaching no longer suffice in this technological world. Currently there are more than 100,000 computers in schoolrooms in the United States. Students mediocre and bright alike, from the first stage through high school not only are not intimidated by my computers, but have become avid participants in the computer epoch.

   Kids operating computer implement their curriculum with great versatility. A music student can program musical notes so that the computer will play Beethoven or the Beatles. For a biology class, the computer can produce a picture of the intricate envisage human biology in a profound way. A nuclear reactor is no longer an enigma to students who can see its workings in minute detail on a computer. In Wisconsi, the Chippewa Indians are studying their ancient and almost forgotten language with the aid of a computer. More commonly, the computer is used for drilling math and language concepts so that youngsters may learn at their own speed without trying the patience of their human teachers. The simplest computers aid the handicapped, who learn more rapidly from the computer than from humans. Once irksome, remedial drills and exercises now on computer are conducive to learning because the machine responds to correct answers with praise and to incorrect answers with frowns and even an occasional tear.

   Adolescents have become so exhilarated by computers that they have developed their own jargon, easily understood by their peers but leaving their disconcerted parents in the dark. They have shown so much fervor for computer that they have formed computer clubs, beguile their leisure hours in computer stores, and even attend computer camps. A Boy Scout can get a computer merit badge. One ingenious young student devised a computer game for Atari will earn him $100,000 in royalties This is definitely the computer age. Manufacturers of computers are presently getting tax write – offs for donating equipment to colleges and universities and are pushing for legislation to obtain further deductions for contributions to elementary and high school. Furthermore, the price of computer for home or office is being sold for less than $100. At that price every class in the country will soon have computer kids.

It can be inferred from the passage that _____________

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 from 31 to 35.
Graphic novels, as the name suggests, are books written and illustrated in the style of a comic book. Adults may feel that graphic novels do not help children become good readers. They believe that this  type of  reading material  somehow prevents  "real"   reading. (31) , many quality graphic novels are now being seen as a method of storytelling on the same level as novels, films or audiobooks. Many librarians and teachers are now accepting graphic novels as proper literature for children as they (32) young people and motivate them to read. This has been especially true with children who are not (33) to read, especially boys.
Language learners are also motivated by graphic novels because the pictures provide clues to the meaning of the words. Therefore, they   will (34) new vocabulary more quickly. Many teachers have reported great success when they used graphic novels with their students, especially in the areas of English, social studies and art. The idea that graphic novels are too simple to be regarded as serious reading is no longer valid. Reading them can, undoubtedly, help students develop the skills (35) are necessary to read more challenging works.
(31).................

Birds that feed in flocks commonly retire together into roosts. The reasons for roosting communally are not always obvious, but there are some likely benefits, In winter especially, it is important for birds to keep warm at night and conserve precious food reserves. One way to do this is to find a sheltered roost. Solitary roosters shelter in dense vegetation or enter a cavity- horned, larks dig holes In the ground and ptarmigan burrow into snow banks- but the effect of sheltering is magnified by several birds huddling together in the roost, as wrens, swifts, brown creepers, bluebirds, and anis do. Body contact reduces the surface area exposed to the cold air, so the birds keep each other warm. Two kinglets huddling together were found to reduce their heat losses by a quarter and three together saved a third of their heat.

The second possible benefit of communal roosts is that they act as "information centers". During the day, parties of birds will have spread out to forage over a very large area. When they return in the evening some will have fed well, but others may have found little to eat. Some investigators have observed that when the birds set out again next morning, those birds that did not feed well on the previous day appear to follow those that did. The behavior of common and lesser kestrels may illustrate different feeding behaviors of similar birds with different roosting habits. The common kestrel hunts vertebrate animals in a small, familiar hunting ground, whereas the very similar lesser kestrel feeds on insects over a large area. The common kestrel roost and hunts alone, but the lesser kestrel roosts and hunts in flocks, possibly so one bird can learn from others where to find insect swarms. Finally, there is safety in numbers at communal roosts since there will always be a few birds awake at any given moment to give the alarm. But this increased protection is partially counteracted by the fact that mass roosts attract predators and are especially vulnerable if they are on the ground. Even those in trees can be attacked by birds of prey. The birds on the edge are at greatest risk since predators find it easier to catch small birds perching at the margins of the roost

What does the passage mainly discuss?

The Influence of Advertising on Pricing
Advertising makes an immense difference in the popularity of a product. Studies have shown that consumers usually pay more for advertised products than non-advertised products. As a result, the marketing and advertising industry is a multibillion-dollar-a-year business. Local commercials can cost as little as several hundred dollars to produce, while national companies have been known to spend hundreds of thousands of dollars on a single commercial. Interestingly, the source for these expensive commercials is the consumers who view the advertisements from the comfort of their living rooms. Companies influence the prices that consumers pay in two ways.
When consumers purchase any product, they are obviously paying for the cost of manufacturing the product. However, they are also paying for the advertising campaign devised to convince consumers to buy the product. The more costly the advertising campaign, the higher the price paid by consumers. Companies are allowed to set these high prices because consumers have shown that they will continue to pay them. For instance, a multinational chain of coffee shops significantly raised its prices a few years ago, due in no small part to an expensive national advertising campaign. While regular customers noticed and were not fond of the hike, one was quoted as saying, “I doubt it will make an impact [on consumers]. It won’t change my habit." Indeed, it did not; the company experienced record sales in spite of the fact its prices were higher than its competitors'.
Another way advertising tends to affect product pricing is seen in the arena of perceived value to the consumers. The perceived value is the worth that consumers assign to a product. Studies show that often the advertising for a product determines its value more than the quality or necessity of the product itself. One way a company may take advantage of this perceived value is by running commercials during prime time. These ads are usually much more expensive than others. For example, a national commercial that ran during a popular American show cost close to $745,000 to run for thirty seconds. If people watching the show perceive that the product is more valuable simply because it was advertised during prime time, they are often willing to pay higher prices. So, whether it is seen in the cost of the commercials or the advertiser-assigned value, it is obvious that advertising drives product pricing and directly affects consumers.

Which of the following is true about the effect of higher-priced ad campaigns?

Birds that feed in flocks commonly retire together into roosts. The reasons for roosting communally are not always obvious, but there are some likely benefits, In winter especially, it is important for birds to keep warm at night and conserve precious food reserves. One way to do this is to find a sheltered roost. Solitary roosters shelter in dense vegetation or enter a cavity- horned, larks dig holes In the ground and ptarmigan burrow into snow banks- but the effect of sheltering is magnified by several birds huddling together in the roost, as wrens, swifts, brown creepers, bluebirds, and anis do. Body contact reduces the surface area exposed to the cold air, so the birds keep each other warm. Two kinglets huddling together were found to reduce their heat losses by a quarter and three together saved a third of their heat.

The second possible benefit of communal roosts is that they act as "information centers". During the day, parties of birds will have spread out to forage over a very large area. When they return in the evening some will have fed well, but others may have found little to eat. Some investigators have observed that when the birds set out again next morning, those birds that did not feed well on the previous day appear to follow those that did. The behavior of common and lesser kestrels may illustrate different feeding behaviors of similar birds with different roosting habits. The common kestrel hunts vertebrate animals in a small, familiar hunting ground, whereas the very similar lesser kestrel feeds on insects over a large area. The common kestrel roost and hunts alone, but the lesser kestrel roosts and hunts in flocks, possibly so one bird can learn from others where to find insect swarms. Finally, there is safety in numbers at communal roosts since there will always be a few birds awake at any given moment to give the alarm. But this increased protection is partially counteracted by the fact that mass roosts attract predators and are especially vulnerable if they are on the ground. Even those in trees can be attacked by birds of prey. The birds on the edge are at greatest risk since predators find it easier to catch small birds perching at the margins of the roost

Which of the following is not mentioned in the passage as an advantage derived by birds that huddle together while sleeping?

During the seventeenth and eighteenth centuries, almost nothing was written about    the contributions of women during the colonial period and the early history of the newly formed United States. Lacking the right to vote and absent from the seats of power, women were not considered an important force in history. Anne Bradstreet wrote some significant poetry in the seventeenth century, Mercy Otis Warren produced the host contemporary    history of the American Revolution, and Abigail Adams penned Important letters showing    she exercised great political Influence over her husband, John, tiie second President of the United States. But little or no notice was taken of these contributions. During those centuries, women remained Invisible In history  books.
Throughout the nineteenth century, this lack of visibility  continued,  despite  the  efforts of female authors writing about women, These writers, like most of their male counterparts, were amateur historians. Their writings were celebratory in  nature,  and  they were uncritical in their selection and use of  sources.
During the nineteenth century, however, certain feminists showed a keen sense of history by keeping records of activities in which women were engaged. National, regional,    and local women's organizations compiled accounts of  their  doings.  Personal  correspondence, newspaper clippings, and souvenirs were saved and stored. These sources  from the core of the two greatest collections of women’s history In the United States one at   the Elizabeth and Arthur Schleslnger Library at Radcliffe College, and the other the Sophia Smith Collection at Smith College. Such sources have provided valuable materials for later Generations of historians.
Despite the gathering of more information about ordinary women during  the  nineteenth Century, most of the writing about women conformed to  the  "great  women"  theory of History, just as much of mainstream American  history  concentrated  on  "great  men," To demonstrate that women were making significant contributions to American life, female authors singled out women leaders and wrote biographies, or else important women produced their autobiographies. Most of these leaders were Involved in public life  as  reformers, activists working for women's right to vote, or authors,  and  were  not  representative at all of the great of ordinary woman. The lives of ordinary people continued, generally, to be untold in the American histories being   published.

The word "representative" in the last paragraph is closest in meaning to .................

The Influence of Advertising on Pricing
Advertising makes an immense difference in the popularity of a product. Studies have shown that consumers usually pay more for advertised products than non-advertised products. As a result, the marketing and advertising industry is a multibillion-dollar-a-year business. Local commercials can cost as little as several hundred dollars to produce, while national companies have been known to spend hundreds of thousands of dollars on a single commercial. Interestingly, the source for these expensive commercials is the consumers who view the advertisements from the comfort of their living rooms. Companies influence the prices that consumers pay in two ways.
When consumers purchase any product, they are obviously paying for the cost of manufacturing the product. However, they are also paying for the advertising campaign devised to convince consumers to buy the product. The more costly the advertising campaign, the higher the price paid by consumers. Companies are allowed to set these high prices because consumers have shown that they will continue to pay them. For instance, a multinational chain of coffee shops significantly raised its prices a few years ago, due in no small part to an expensive national advertising campaign. While regular customers noticed and were not fond of the hike, one was quoted as saying, “I doubt it will make an impact [on consumers]. It won’t change my habit." Indeed, it did not; the company experienced record sales in spite of the fact its prices were higher than its competitors'.
Another way advertising tends to affect product pricing is seen in the arena of perceived value to the consumers. The perceived value is the worth that consumers assign to a product. Studies show that often the advertising for a product determines its value more than the quality or necessity of the product itself. One way a company may take advantage of this perceived value is by running commercials during prime time. These ads are usually much more expensive than others. For example, a national commercial that ran during a popular American show cost close to $745,000 to run for thirty seconds. If people watching the show perceive that the product is more valuable simply because it was advertised during prime time, they are often willing to pay higher prices. So, whether it is seen in the cost of the commercials or the advertiser-assigned value, it is obvious that advertising drives product pricing and directly affects consumers.

Which of the following can be inferred about pricing and advertising?

Although they are an inexpensive supplier of vitamins, minerals, and high-quality protein, eggs also contain  a high  level of blood cholesterol, one of the major causes of heart diseases. One egg   yolk, in fact, contains a little more than two-thirds of the suggested daily cholesterol limit. This knowledge has caused egg sales to plummet in recent years, which in turn has brought about the development of several alternatives to eating regular eggs. One alternative is to eat substitute eggs. These egg substitutes are not really eggs, but they look somewhat like eggs when  they are  cooked. They have the advantage of having low cholesterol rates, and they can be  scrambled  or  used  in baking. One disadvantage, however, is that they are not good for frying, poaching,  or boiling.  A second alternative to regular eggs is a new type of egg, sometimes called 'designer' eggs. These eggs  are produced by hens that are fed low-fat diets consisting of Ingredients such as canola oil, flax, and rice bran. In spite of their diets, however, these hens produce eggs that contain the same amount of cholesterol as regular eggs. Yet, the producers of these eggs claim that eating their eggs will not raise the blood cholesterol in  humans.
Egg producers  claim  that their product has been  portrayed unfairly. They cite scientific studies  to back up their claim. And, in fact, studies on the relationship between eggs and human cholesterol levels have brought mixed results. It may be that it is not the type of egg that is the main determinant   of cholesterol but the person who is eating the eggs. Some people may be  more  sensitive  to  cholesterol derived from food than other people. In fact, there is evidence that certain dietary fats stimulate the body's production of blood cholesterol. Consequently, while it still makes sense to limit one's intake of eggs, even designer eggs, it seems that doing this without regulating dietary fat will probably not help reduce the blood cholesterol  level.

What is the meaning of 'back up'?

Some animal behaviorists argue that certain animals can remember past events, anticipate future ones, make plans and choices, and coordinate activities within a group. These scientists, however, are cautious about the extent to which animals can be credited with conscious   processing.
Explanations of animal behavior that leave out any sort of consciousness at all and ascribe actions entirely to instinct leave many questions unanswered. One example of such unexplained behavior: Honeybees communicate the sources of nectar to one another by doing a dance in a figure-eight pattern. The orientation of the dance conveys the position of the food relative to the sun's position in the sky, and the speed of the dance tells how  far  the food source is from  the  hive. Most researchers assume that the ability to perform and  encode the dance is innate and  shows no special intelligence. But in one study, when experimenters kept changing the site of     the food source, each time moving the food 25 percent father from the previous site, foraging honeybees began to anticipate where the food source would appear next. When the researchers arrived at the new location, they would find the bees circling the spot, waiting for their food. No one has yet explained how bees, whose brains weigh four ten-thousandths of an  ounce,  could  have inferred the location of the new  site.
Other behaviors that may indicate some cognition include tool use. Many animals, like the otter who uses a stone to crack mussel shells, are capable of using objects in the natural environment as rudimentary tools. One researcher has found that mother  chimpanzees  occasionally show their young how to use tools to open hard nuts. In one study, chimpanzees compared two pairs of food wells containing chocolate chips. One pair might contain, say, five chips and three chips, the other four chips and three chips. Allowed to choose which pair they wanted, the  chimpanzees  almost always chose the  one with the higher total, showing some sort  of summing ability. Other chimpanzees have learned to use numerals to label quantities of items and do simple sums.

What did researchers  discover in the study of honeybees discussed in paragraph 2?