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Don't be afraid ____ me if you have any further queries.

 

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Leonardo da Vinci was born on April 15, 1452, in the small Tuscan town of Vinci,  near Florence. Leonardo was the son of a wealthy Florentine public official and a peasant woman. In the mid- 1460s, the family settled in Florence, where Leonardo was given the best education that Florence could offer. He rapidly advanced socially and intellectually. He was handsome, persuasive in conversation and a fine musician and improviser. About in 1466, he apprenticed as a studio boy to Andrea Del Verrocchio. In Verrocchio’s workshop, Leonardo was introduced to many activities, from the painting of altarpieces and panel pictures to the creation of large sculptural projects. In 1472, he was entered in the painter’s guild of Florence, and in 1476, he was still mentioned as Verrocchio’s assistant. In Verrocchio’s Baptism of Christ, the kneeling angel at the left of the painting is by Leonardo.  In 1478, Leonardo became an independent master. His first commission, to paint an altarpiece for the chapel of the Palazzo Vecchino, the Florentine town hall, was never executed. His first large painting, The Adoration of the Magi, left unfinished, was ordered in 1481 for the Monastery of San Donato a Scopeto, Florence. Other works ascribed to his youth are the so-called Benois Madonna, the portrait Ginerva de’ Benci, and the unfinished Saint Jerome.  In 1482, Leonardo’s career moved into high gear when he entered the service of the duke of Milan, Ludovico Sforza, having written the duke an astonishing letter in which he stated that he could build portable bridges; that he knew the techniques of constructing bombardments and of making cannons; that he could build ships as well as armored vehicles, catapults, and other war machines; and that he could execute sculpture in marble, bronze, and clay. He served as a principal engineer in the duke’s numerous military enterprises and was so active also as an architect. In addition, he assisted the Italian mathematician Luca Pacioli in the celebrated work Divina Proportione.  Evidence indicates that Leonardo had apprentices and pupils in Milan, for whom he probably wrote the various texts later compiled as Treatise on Painting. The most important of his own paintings during the early Milan period was The Virgin of the Rocks, two versions of which exist; he worked on the compositions for a long time, as was his custom, seemingly unwilling to finish what he had begun.  From 1495 to 1496, Leonardo labored on his masterpiece, The Last Super, a mural in the refectory of the Monastery of Santa Maria Delle Grazie, Milan. Unfortunately, his experimental use of oil on dry plaster was technically unsound, and by 1500 its deterioration had begun. Since 1726 attempts have been made, unsuccessfully, to restore it; a concerted restoration and conservation program, making use of the latest technology, was begun in 1977 and is reversing some of the damage. Although much of the original surface is gone, the majesty of the composition and the penetrating characterization of the figures give a fleeting vision of its vanished splendor.  During his long stay in Milan, Leonardo also produced other paintings and drawings, most of which have been lost theater designs, architectural drawings, and models for the dome of Milan Cathedral. His largest commission was for a colossal bronze monument to Francesco Sforza, father of Ludovico, in the courtyard of Castello Sforzesco. In December 1499, however, the Sforza family was driven from Milan by French forces; Leonardo left the statue unfinished and he returned to Florence in 1500.
3. The word “catapults” in paragraph 3 is probably __________

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When another old cave is discovered in the south of France, it is not usually news.
Rather, it is an ordinary event. Such discoveries are so frequent these days that hardly anybody pays heed to them. However, when the Lascaux cave complex was discovered in 1940, the world was amazed. Painted directly on its walls were hundreds of scenes showing how people lived thousands of years ago. The scenes show people hunting animals, such as bison or wild cats.
Other images depict birds and, most noticeably, horses, which appear in more than 300 wall images, by far outnumbering all other animals.
Early artists drawing these animals accomplished a monumental and difficult task. “They” did not limit themselves to the easily accessible walls but carried their painting materials to spaces that required climbing steep walls or crawling into narrow passages in the Lascaux complex.
Unfortunately, the paintings have been exposed to the destructive action of water and temperature changes, which easily wear the images away. Because the Lascaux caves have many entrances, air movement has also damaged the images inside. Although they are not out in the open air, where natural light would have destroyed them long ago, many of the images have deteriorated and are barely recognizable. To prevent further damage, the site was closed to tourists in 1963, 23 years after it was discovered.

What does the passage say happened at the Lascaux caves in 1963?

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For many years, scientists have speculated that the cataclysmic impact of an asteroid with the earth was responsible for the demise of the dinosaurs approximately 65 million years ago. Previous discoveries and results have hinted that an asteroid two kilometers in diameter struck the Yucatan peninsula in Eastern Mexico. This impact, stronger than one thousand nuclear explosions, is speculated to have cast a cloud of dust and debris into the atmosphere, covering the entire surface of the earth and blocking out the sun and consequently lowering the surface temperature of the earth. With such a radical change in the earth's environment, scientists believe that over 99% of all animal and plant species were eradicated. Only after millions of years did plants and animals even begin to recover and develop into forms that were better adapted to survive changes in their environment. But, the reign of the dinosaurs had ended and the age of mammals had begun. The crucial link that has held this theory together has been the element iridium. Iridium is not commonly found on either the surface of the earth or inside the crust. It is more commonly found in asteroids or meteorites throughout the solar system. Scientists have hypothesized that after the asteroid impacted the Earth, an even layer of iridium sediment settled over the globe and eventually became part of its surface. The theory, of course, has depended on the discovery of such an existing layer of iridium. Unfortunately, scientists have never been able to offer absolute proof that this asteroid impact ever occurred. Recently, however, a discovery may go a long way toward validating these scientists 'theories. In 1996, a team of marine biologists excavated samples of rock from the Atlantic Ocean just off the cost of Bermuda. Found thousands of meters below the sea, these samples contain iridium similar to those found in the Yucatan peninsula thousands of kilometers away. At first, scientists were skeptical whether the samples were from the same time period. But since carbon dating placed them to 65 million years ago, their doubts were quickly alleviated. Since then many of the other theories for the demise of the dinosaur have been finally laid to rest.
3. The word "hinted" is closest in meaning to: 

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Rogue waves are extremely large waves that are more than double the average height of most waves. According to mathematical calculations and various personal accounts, rogue waves can reach remarkable heights. They appear unexpectedly in calm waters and can do major damage, even to large ships. Unlike tsunamis, which are practically undetectable in deep water, rogue waves only occur far out at sea. Stories about rogue waves have circulated amongst sailors for centuries, but it was not until recently that scientists confirmed they actually exist. What they still are not sure of, however, is what causes them. Some instances of rogue waves have been explained by the interactions of normal wave patterns with ocean currents. Scientists believe that it is possible for waves to reach the heights described when they come into contact with strong ocean currents. The wave heights increase significantly when a normal wave reaches a current head on. In other words, the wave is built up by the power of the current. This explanation was first proposed after scientists observed a high incidence of rogue waves in the ocean surrounding the southern tip of Africa. In fact, since 1990, at least twenty ships have encountered the waves, which reportedly reached up to 190 feet. The waves are thought to be caused by wave interactions with the strong Agulhas Current, which runs southbound along the east coast of the continent.  
1. The passage mainly discusses __________

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Learning shouldn’t end when you reach a certain point in your career; it should be something you continuously pursue across your lifetime. As you mature, your areas of interest may change. Perhaps your personal and career goals may morph into something altogether different than what you originally intended. In some cases, life happens and you might find it necessary to take a break from your career or your education. But for people with a strong desire for lifelong learning, this pause is only temporary. Even though you may have begun an educational program and needed to take a pause later, it’s never too late to go back and finish what you started. People in modern age have more options to gain the knowledge they want and need. From a higher education standpoint, universities and colleges are working hard to transform themselves in different ways. For example, there has been a transition from traditional Ph.D.-style doctorates to applied doctorates like the Doctorate in Strategic Intelligence or Doctorate in Global Security. These academic programs have their students work to address real-world problems of practice. In this manner, they take the education they receive in their classes and work to apply it within the fields in which they are currently employed or hope to work in. In addition, some universities now offer dual degree programs, such as the dual master’s degree in emergency and disaster management and homeland security. Some institutions are also starting to provide accelerated degrees to allow their students to rapidly advance from a B.A. to an M.A., saving those students time and money on their educational pursuits. However, lifelong learning doesn’t just encompass full degree programs. With employers focusing on skillset development, there is an increasing desire for short program offerings as well. “Short programming” includes sets of courses that lead to a specific credential or badge. For instance, ASIS International offers a series of certifications, related to security and global studies, which can be used to add value to your professional portfolio. Another relevant certification is the Certified Threat Manager (CTM) certification offered by the Association of Threat Assessment Professionals. Short programming involves learning tracks, competency-based micro-credentials or stackable credentials. In some cases, certificates are perceived to be more valuable as they signal that their owner has current knowledge of a particular area; however, this perception differs from field to field
7. Which of the following statements is TRUE, according to the passage?

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Stories about how people (1)__________ know when they are being watched have  been going around for years. However, few made have been made to investigate the phenomenon scientifically. Now, with the completion of the largest ever study of the socalled staring effect, there is impressive evidence that this is a recognizable and (2) _______ sixth sense. The study involved hundreds of children. For the experiments, they sat with their eyes covered and with their backs to other children, who were told to either stare at them or look away. The results consistently showed that the children who could not see were able to (3) _______ when they were being stared at. In a total of 18,000 trials carried out worldwide, the children correctly sensed when they were being watched almost 70% of the time. The experiment was repeated with the added precaution of putting the children who were being watched outside the room, (4) _______ from the starters by the windows. The results, though less impressive, were more or less the same. Dr. Sheldrake, the biologist who designed the study, believes that the results are (5) _______ enough to find out through further experiments precisely how the staring effect might actually come about.

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An individual’s personality is the complex of mental characteristics that makes them unique from other people. It includes all of the patterns of thought and emotions that cause us to do and say things in particular ways. At a basic level, personality is expressed through our temperament or emotional tone. However, personality also colors our values, beliefs, and expectations. There are many potential factors that are involved in shaping a personality. These factors are usually seen as coming from heredity and the environment. Research by psychologists over the last several decades has increasingly pointed to hereditary factors being more important, especially for basic personality traits such as emotional tone. However, the acquisition of values, beliefs, and expectations seem to be due more to socialization and unique experiences, especially during childhood. Some hereditary factors that contribute to personality development do so as a result of interactions with the particular social environment in which people live. For instance, your genetically inherited physical and mental capabilities have an impact on how others see you and, subsequently, how you see yourself. Likewise, your health and physical appearance are likely to be very important in your personality development. You may be frail or robust. You may have a learning disability. You may be slender in a culture that considers obesity attractive or vice versa. These largely hereditary factors are likely to cause you to feel that you are nice-looking, ugly, or just adequate. Likewise, skin color, gender, and sexual orientation are likely to have a major impact on how you perceive yourself. Whether you are accepted by others as being normal or abnormal can lead you to think and act in a socially acceptable or marginal and even deviant way. There are many potential environmental influences that help to shape personality. Child rearing practices are especially critical. In the dominant culture of North America, children are usually raised in ways that encourage them to become self-reliant and independent. Children are often allowed to act somewhat like equals to their parents. Children are given allowances and small jobs around the house to teach them how to be responsible for themselves. In contrast, children in China are usually encouraged to think and act as a member of their family and to suppress their own wishes when they are in conflict with the needs of the family. Independence and self-reliance are viewed as an indication of family failure and are discouraged.
8. According to the passage, what is valued in one society may _____ 

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An individual’s personality is the complex of mental characteristics that makes them unique from other people. It includes all of the patterns of thought and emotions that cause us to do and say things in particular ways. At a basic level, personality is expressed through our temperament or emotional tone. However, personality also colors our values, beliefs, and expectations. There are many potential factors that are involved in shaping a personality. These factors are usually seen as coming from heredity and the environment. Research by psychologists over the last several decades has increasingly pointed to hereditary factors being more important, especially for basic personality traits such as emotional tone. However, the acquisition of values, beliefs, and expectations seem to be due more to socialization and unique experiences, especially during childhood. Some hereditary factors that contribute to personality development do so as a result of interactions with the particular social environment in which people live. For instance, your genetically inherited physical and mental capabilities have an impact on how others see you and, subsequently, how you see yourself. Likewise, your health and physical appearance are likely to be very important in your personality development. You may be frail or robust. You may have a learning disability. You may be slender in a culture that considers obesity attractive or vice versa. These largely hereditary factors are likely to cause you to feel that you are nice-looking, ugly, or just adequate. Likewise, skin color, gender, and sexual orientation are likely to have a major impact on how you perceive yourself. Whether you are accepted by others as being normal or abnormal can lead you to think and act in a socially acceptable or marginal and even deviant way. There are many potential environmental influences that help to shape personality. Child rearing practices are especially critical. In the dominant culture of North America, children are usually raised in ways that encourage them to become self-reliant and independent. Children are often allowed to act somewhat like equals to their parents. Children are given allowances and small jobs around the house to teach them how to be responsible for themselves. In contrast, children in China are usually encouraged to think and act as a member of their family and to suppress their own wishes when they are in conflict with the needs of the family. Independence and self-reliance are viewed as an indication of family failure and are discouraged.
7. According to the passage, what is the most important environmental factor in personality development?

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………… have enough apples, she’ll make an apple pie this afternoon.

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Gujarat’s favourite watering hole, Union territory of Daman, will add more activity  for its tourists than let them hang around only in the bars on its sun-kissed beaches. The administration has decided to develop leisure water sports on Jampore and Light house beaches at Moti Daman. The tourism department of Daman has already selected two operators to run these leisure water sports facilities. At present, facilities like creation of ramps, walking area and waiting area for the tourists are under construction at the beaches.  Director of Daman Tourism, Harshil Jain told TOI, “The leisure water sports activities are all set to start very soon. We have not decided the dates, but the contractors are working day-and-night to set up facilities soon at both the beaches.” He further said that leisure water sports will help boost tourism in Daman. “The flow of tourist will increase during the vacation period. Till now, tourists come here to enjoy sitting on the beaches, but now they will have the option for water sports, too,” Jain added.  According to tourism department officials, the sporting activity would be set up on the lines of Goa. Attractions like jet skis, banana ride, para sailing, pedal boating, rowing, kayaking and motorboating will add to the beach fun, they said. A senior tourism officer said, “Since adventure has a risk factor, we have asked the contractors to keep provision of accidental insurance cover for all the tourists using the ride. Customers too must be covered for accidental death, loss of limb and permanent and partial disability.” “On the weekends alone, more than 60,000 people visit Daman. We are pretty sure that the water sports activity will increase the numbers to more than 80,000,” asserted another official. 
1. Which best serves as the title for the passage?

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When Tony Stark dazzled audiences by designing his Iron Man suit by simply picking  up and chucking up holographic virtual gear in mid air instead of being hunched over a computer it was a perfect teaser into the future of gesture-based computing. What’s even more exciting is that most of this technology is already available and is set to go mainstream. Gesture-based computing is interacting with computers through nontraditional interfaces using the body instead of the mouse and the keyboard. It allows users to have no physical contact with a device and yet interact with it just as they would with traditional interfaces. The most widely used of gesture-based computing devices and already a huge commercial success is the Kinect. Thanks to some amazing software that could extrapolate missing body parts and even tell different users apart, it went on to become a hit among gamers looking for the next big thing to enhance their gaming experience. The Kinect works by being able to map a body and produce a digital reproduction of a body’s shape, skeletal outline and even facial details that gives developers access to unlimited possibilities for interfaces and applications.  Another big contender in the gesture computing revolution is the Leap motion. Leap motion takes gesture-based computing to finger precision perfection. It reads gestures within a 8 cubic feet volume and any motion of the hand or fingers can be tracked to 1/100th of a millimeter, heralding exciting possibilities about its use with applications that require a higher degree of accuracy.  Gesture-based computing is now ripe to be a part of gaming, TVs, devices, kiosks, medical, 3D sculpting, engineering, medical professionals, designers, advertisers and even people with physical disabilities.
4. The word “it” in paragraph 2 refers to _______

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Just as optical fibers have transformed communication, they are also revolutionizing medicine. These ultra - thin, flxible fiers have opened a window into the living tissues of the body. By inserting optical fibers through natural openings or small incisions and the threading them along the body's established pathways, physicians can look into the lungs, intestines, heart and other areas that were formerly inaccessible to them. The basic fiber-optics system is called fiberscope, which consists of two bundles of fibers. One, the illuminating bundle, carries light to the tissues. It is coupled to a high-intensity light source. Light enters the cores of the high-purity silicon glass and travels along the fibers. A lens at the end of the bundle collects the light and focuses it into the other bundle, the imaging bundle. Each fibers in the bundle transmits only a tiny fraction of the total image. The reconstructed image can be viewed through an eyepiece or displayed on a television screen. During the last five years, improved methods of fabricating optical fibers have led to a reduction in fiberscope diameter and an increase in the number of fibers, which in turn has increased resolution. Optical fibers can also be used to deliver laser light. By use of laser beams, physicians can perform surgery inside the body, sometimes eliminating the need of invasive procedures in which healthy tissue must be cut through to reach the site of disease. Many of these procedures do not require anesthesia and can be performed in a physician's office. These techniques have reduced the risk and the cost of medical care.
6. Which of the following is closest in meaning to the word "cores"?

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If you want to spend your time effectively, you can try the following tips. First, make a to-do list every day. Put the most important tasks at the top, even if  they’re things you’re dreading, and tackle them first. Include things you want to do on your list too, so you have items you’re looking forward to. Try motivating yourself with a reward if you get to everything on your list.  Once you know what you need to do, keep your work with you. That way, if you find yourself with extra time – while in the train or bus or waiting for an appointment – you can get something done.  Additionally, don’t be afraid to say no. It’s OK to say no if your friend asks you to go to a movie one night but you have a test the next morning. Instead, find a time that works for both of you and go to see the movie then.  Managing your time also includes finding you productive time. Are you a morning person or a night person? You’ll be more efficient of you work when you’re at your best.  Last but not least, create a dedicated study time. Set up a time devoted only to studying or homework. Shut off you phone and respond to calls or texts when your work is finished. Don’t check email or surf the web (except when you need to for the work you’re doing) during this time either. 
5. What is NOT mentioned as an activity to avoid during study time?

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The world is losing languages at an alarming rate. Michael Krauss suggested that of the approximately 6,000 human languages alive today, only 350 to 500 are safe from extinction. Some linguists estimate that a language dies every two weeks or so. At the current rate, by 2100, about 2,500 native languages could disappear. Languages become extinct for many reasons. Through imperialism, colonizers impose their languages on colonies. Some politicians believe multilingualism will fragment national interests. Thus they prohibit education in all but the national language. Another reason for language death is the spread of more powerful languages. In the world today, several languages, including English, are so dominant in commerce, science, and education, that languages with fewer speakers have trouble competing. Although in the past, governments have been one of the primary causes of language death, many have now become champions of preserving endangered languages and have had some significant successes. Two outstanding examples are the revival of Hebrew and Irish. Hebrew was considered a dead language, like Latin, but is now the national language of Israel. Irish was not dead, but severely threatened by English when the government of Ireland began its rescue immediately after the establishment of the Irish Free State in 1922. All students in public schools must now take some classes in Irish and there are Irish programs in major media, such as television and radio. According to the Irish government, approximately 37% of the population of Ireland now speaks Irish. One of the largest programs to revive languages, Documenting Endangered Languages (DEL), is being conducted by three U.S. government agencies: the National Science Foundation, the National Endowment for the Humanities, and the National Museum of Natural History. Researchers funded by these agencies are recording interviews with the mostly elderly people who still speak the languages. Analyses of these interviews will help linguists publish dictionaries and grammars of the languages. Eventually, linguists hope to establish language-training programs where younger people can learn the languages, carrying them on into the future. The linguists participating in DEL defend spending millions of dollars to preserve dying languages. They point out that when a language dies, humanity loses all of the knowledge of the world that that culture held. Traditional healers in rural areas have given scientists important leads in finding new medicines; aspirin is an example of these. But one of the most common reasons given by these researchers is that studying languages gives us insight into the radically different way humans organize their world. David Lightfoot, an official at the National Science foundation, gives the example of Guguyimadjir, and Australian aboriginal language, in which there are no words for “right” or left,” only for “north,” “south,” “east,” and “west.” Many researchers are optimistic that the efforts to save dying languages will succeed, at least in part. Bruce L. Cole, Chairman of the National Endowment for the Humanities, said, “Not only is this a time of great potential loss, it is also a moment for enormous potential gain. In this modern age of computers and our growing technological capabilities, we can preserve, assemble, analyze, and understand unprecedented riches of linguistic and cultural information.”
4. The word “revive” in paragraph 4 mostly means _______

Mark the letter A, B, C, or D on your answer sheet to indicate the undelined part that needs correction in each of the following questions:
In the United States, it is important to be on time, or punctual, for an appointment, a class, a meeting, etc... This may not be true in some other countries, however. An American professor discovered this difference while teaching a class in a Brazilian university. The two-hour class was scheduled to begin at 10 a.m, and end at 12 a.m. On the first day, when the professor arrived on time, no one was in the classroom. Many students came after 11 a.m. Although all of the students greeted the professor as they arrived, few apologised for their lateness. Were these students being rude? He decided to study the students’ behavior.
In American university, students are expected to arrive at the appointed hour. On the other hand, in Brazil, neither the teacher nor the students always arrive at the appointed hour. Classes not only begin at the scheduled time in the United States, but they also end at the scheduled time. In the Brazilian class, only a few students left the class at noon, many remained past 12:30 to discuss the class and ask more questions. While arriving late may not be important in Brazil, neither is staying late.
The explanation for these differences is complicated. People from Brazilian and North American cultures have different feelings about lateness. In Brazil, the students believe that a person who usually arrives late is probably more successful than a person who is always on time. In fact, Brazilians expect a person with status or prestige to arrive late, while in the United States, lateness is usually considered to be disrespectful and unacceptable. Consequently, if a Brazilian is late for an appointment with a North America, the American may misinterpret the reason for the lateness and become angry.
As a result for his study, the professor learned that the Brazilian students were not being disrespectful to him. Instead, they were simply behaving the appropriate way for a Brazilian student in Brazil. Eventually, the professor was able to adapt his own behavior to feel comfortable in the new culture.

All of these following sentences are true for the first day of the professor in Brazil EXCEPT     

Each sentence has a mistake. Find it by choosing the letter A, B, C or D.

Reading brings a variety of benefits because of readers can gain many lessons and much knowledge from books.

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Jakarta is the capital of Indonesia. Today Jakarta has much to offer, ranging from museums, art and (1) ________markets, first class shopping to accommodations and a wide variety of cultural activities. Jakarta’s most famous (2) ______, the National Monument or Monas is a 137m obelisk topped with a flame sculpture coated with 35 kg of gold. Among other places one can mention the National museum that holds an extensive collection of ethnographic artifacts and relics, the Maritime Museum that (3) ______ Indonesia’s seafaring traditions, including models of sea going vessels. Jakarta has a distinctly cosmopolitan flavor. Tantalize your taste buds with a gastronomic spree around the city’s many eateries. Like French gourmet dining, exotic Asian cuisine, American fast food, stylish cafes, restaurant all (4) _____ to find a way into your heart through your stomach. The taste of Indonesia’s many cultures can be found in (5)______ any corner of the city: hot and spicy food from West Sumatra, sweet tastes of Dental Java, the tangy fish dishes of North Sulawesi

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Once restricted to space stations and satellites, photovoltaics are now gaining popularity and becoming an increasingly viable option. Every day, the sun releases an enormous amount of energy, far more than the entire population consumes. Being that the sun is a sustainable, renewable, and inexhaustible source for generating electricity, not using it seems almost counter-intuitive, especially considering the social and environmental impacts of other forms of energy generation. But the technology to create electricity from the sun is by no means simple and still has some limitations, the most significant being price. The process of turning the sun’s rays into electrical energy all starts in the so-called photovoltaic cell. These cells are produced with two chemically altered silicon layers of which one is missing elections and the other is electron-overloaded. When the photons from the sunlight reach the surface, these electrons gain the ability to move, generating a flow that creates an electric current. Each cell generates a small amount of energy and a panel is usually made of between 36 and 72 photovoltaic cells. By connecting several panels together, a photovoltaic system is created. Eight to ten panels is enough to power a small house. Evidently, however, this statistic is influenced by some factors, such as the efficiency of the panels, the amount of sunshine in the region, and the energy demand of the residence itself.  Importantly, photovoltaic solar panels produce electricity in the form of direct current, meaning the electricity must pass through an inverter to transform it into alternating current - which is what is normally used in buildings, appliances, sockets, and light bulbs. Photovoltaic systems can facilitate energy generation in remote locations where infrastructural networks do not reach. In these cases, the system uses batteries to store electricity when less energy is used than is consumed, such as at night or on very cloudy days. However, it is also possible to use photovoltaics in systems connected to the power grid. In these cases, the excess energy goes to the electricity grid, creating energy “credits” for the building in question. In some countries, it is even possible to sell surplus energy, making the building a power plant for neighbors and method of paying off the investment more quickly.  
3. According to paragraph 1, why is overlooking solar energy considered such a mistake?

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 following questions:
The ruined temples of Angkor are perhaps one of the most impressive Seven Wonders of the World. Located in modern day Cambodia near Lake Tonle Sap, the largest freshwater lake in Asia, Angkor was the seat of power for the Khmer Empire for the ninth to the fifteenth century. The ruins of Angkor are documented as some of the most impressive ones in the world, rivaling the pyramids of Giza in Egypt. Why this mighty civilization died out is a question that archaeologists are now only beginning to ponder. The answer, it turns out, may be linked with the availability of fresh water.
One possible explanation for the downfall of the Khmer Empire has to do with the inhabitant’s irrigation system. The temples and palaces of Angkor were constructed around a series of artificial reservoirs and canals which were annually flooded to capacity by the Mekong River. Once filled, they were used to irrigate the surrounding paddies and farmland during the course of the year. Farmers were completely dependent on the water for their crucial rice crop. Without consistent irrigation, the farmers would have been unable to maintain functional crop production.
Scientists speculate that toward the end of the Khmer Empire the hydraulic system of the reservoirs and canals broke down. The construction of hundreds of sandstone temples and palaces required an enormous amount of physical labor. In addition, as the capital of Khmer Empire, Angkor contained upwards of one hundred thousand people who resided in and around Angkor. In order to feed so many people, the local farmers were driven to grow food more quickly and more efficiently. After centuries of continual use, the irrigation system was pushed beyond its capacity. Soil erosion, nutrient depletion, and loss of water led to decrease in the food supply. With the less food available, the people of Angkor slowly began to migrate to other parts of Cambodia, thus leaving the marvelous city of Angkor to be swallowed by the jungle. Therefore, it is speculated that the Khmer Empire may have fallen victim to its own decrepit infrastructure.

What is the passage mainly about?