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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. The quest for sustainable sources of energy study the energy has led humans to study the energy potential of the sun and the wind, as well as the immense power created by dammed rivers. The oceans, too, represent an impressive source of potential energy. For example, it has been estimated that the oceans could provide nearly 3,000 times the energy generated by hydroelectric dams such as the Hoover Dam. Yet, this source remains quite difficult to exploit. But this challenge has not prevented scientists from trying. Within the last few decades, several technologies that can transform the ocean’s immense forces into usable electricity have been invented and introduced. Some focus on capturing the power of the changing tides, while others rely on thermal energy created by oceans in certain tropical regions. However, the most common and easiest-to-develop technologies are those designed to harness the power inherent in the ocean’s waves. There are several methods by which ocean-wave energy can be collected. All of them work because the movement of the water that the waves induce creates storable energy by directly or indirectly driving a power generator. In one such technology, the changing water levels in the ocean that are produced by waves lift a long floating tube comprised of many sections connected by hinges. As the sections move up and down with the water, they pump a special fluid through the tube that can be used to drive a generator. Another technique works on a similar principle, only the floating object rocks back and forth with the motion of the water instead of up and down. A third method of collecting wave energy relies on the rising water from the waves to compress air in a partially submerged chamber. As the waves rush into the chamber, they push the air out through a narrow tunnel. Located inside this tunnel is a turbine connected to a power generator. The movement of the air turns the turbine, which feeds energy into the generator. The drawback to each of these concepts is that the they make it necessary to have many pieces of machinery linked together. This presents a problem because the larger the device, the more vulnerable it is to damage from hazardous ocean environments, and the more likely it is to interfere with otherwise unspoiled coastal scenery. Also, these methods demand the construction of site-specific machines that take into consideration average local wave heights and sea conditions. Such a requirement can be quite cost-prohibitive, because engineers must create unique power generation mechanism for each site. In other words, the ability to get power from waves differ from region to region. Japan, Norway, and the UK have attempted to generate energy by capturing the power of ocean waves. In northern Scotland, the first power plan to use wave power, OSPREY ( Ocean Swell Powered Renewable Energy ), began operating in 1995. It followed the principle of the third method described above : waves entering a partially submerged chamber pushed air into turbines to generate electricity. The electricity was then transmitted to power collectors in the shore via underwater cables. Unfortunately, the OSPREY plant was destroyed in a large storm, highlighting an unavoidable difficulty associated with this kind of power generation. The potential benefits of wave-based energy are hard to ignore. Once the proper machinery is produced and installed, the energy is free. Maintenance cost are small, and the equipment does not pose any threats of environmental pollution. And best of all, the amounts of energy produced are enormous. However, these theoretical advantages have yet to be fully realized. In many cases, a lack of government funding has inhibited the technologies from advancing. For example, despite the relative abundance of proposed wave-power devices, many have not been adequately tested, and most have been evaluated only in artificial pools where they are not subjected to the harsh marine conditions that exist in actual oceans. Protecting the equipment from the sea’s destructive forces, as well as the fundamental task of determining feasible locations for collecting energy source are substantial and will require more time to overcome.All of these are problems associated with the collection of wave energy EXCEPT ?
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. The quest for sustainable sources of energy study the energy has led humans to study the energy potential of the sun and the wind, as well as the immense power created by dammed rivers. The oceans, too, represent an impressive source of potential energy. For example, it has been estimated that the oceans could provide nearly 3,000 times the energy generated by hydroelectric dams such as the Hoover Dam. Yet, this source remains quite difficult to exploit. But this challenge has not prevented scientists from trying. Within the last few decades, several technologies that can transform the ocean’s immense forces into usable electricity have been invented and introduced. Some focus on capturing the power of the changing tides, while others rely on thermal energy created by oceans in certain tropical regions. However, the most common and easiest-to-develop technologies are those designed to harness the power inherent in the ocean’s waves. There are several methods by which ocean-wave energy can be collected. All of them work because the movement of the water that the waves induce creates storable energy by directly or indirectly driving a power generator. In one such technology, the changing water levels in the ocean that are produced by waves lift a long floating tube comprised of many sections connected by hinges. As the sections move up and down with the water, they pump a special fluid through the tube that can be used to drive a generator. Another technique works on a similar principle, only the floating object rocks back and forth with the motion of the water instead of up and down. A third method of collecting wave energy relies on the rising water from the waves to compress air in a partially submerged chamber. As the waves rush into the chamber, they push the air out through a narrow tunnel. Located inside this tunnel is a turbine connected to a power generator. The movement of the air turns the turbine, which feeds energy into the generator. The drawback to each of these concepts is that the they make it necessary to have many pieces of machinery linked together. This presents a problem because the larger the device, the more vulnerable it is to damage from hazardous ocean environments, and the more likely it is to interfere with otherwise unspoiled coastal scenery. Also, these methods demand the construction of site-specific machines that take into consideration average local wave heights and sea conditions. Such a requirement can be quite cost-prohibitive, because engineers must create unique power generation mechanism for each site. In other words, the ability to get power from waves differ from region to region. Japan, Norway, and the UK have attempted to generate energy by capturing the power of ocean waves. In northern Scotland, the first power plan to use wave power, OSPREY ( Ocean Swell Powered Renewable Energy ), began operating in 1995. It followed the principle of the third method described above : waves entering a partially submerged chamber pushed air into turbines to generate electricity. The electricity was then transmitted to power collectors in the shore via underwater cables. Unfortunately, the OSPREY plant was destroyed in a large storm, highlighting an unavoidable difficulty associated with this kind of power generation. The potential benefits of wave-based energy are hard to ignore. Once the proper machinery is produced and installed, the energy is free. Maintenance cost are small, and the equipment does not pose any threats of environmental pollution. And best of all, the amounts of energy produced are enormous. However, these theoretical advantages have yet to be fully realized. In many cases, a lack of government funding has inhibited the technologies from advancing. For example, despite the relative abundance of proposed wave-power devices, many have not been adequately tested, and most have been evaluated only in artificial pools where they are not subjected to the harsh marine conditions that exist in actual oceans. Protecting the equipment from the sea’s destructive forces, as well as the fundamental task of determining feasible locations for collecting energy source are substantial and will require more time to overcome.The word inhibited in the passage is closest in meaning 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. The quest for sustainable sources of energy study the energy has led humans to study the energy potential of the sun and the wind, as well as the immense power created by dammed rivers. The oceans, too, represent an impressive source of potential energy. For example, it has been estimated that the oceans could provide nearly 3,000 times the energy generated by hydroelectric dams such as the Hoover Dam. Yet, this source remains quite difficult to exploit. But this challenge has not prevented scientists from trying. Within the last few decades, several technologies that can transform the ocean’s immense forces into usable electricity have been invented and introduced. Some focus on capturing the power of the changing tides, while others rely on thermal energy created by oceans in certain tropical regions. However, the most common and easiest-to-develop technologies are those designed to harness the power inherent in the ocean’s waves. There are several methods by which ocean-wave energy can be collected. All of them work because the movement of the water that the waves induce creates storable energy by directly or indirectly driving a power generator. In one such technology, the changing water levels in the ocean that are produced by waves lift a long floating tube comprised of many sections connected by hinges. As the sections move up and down with the water, they pump a special fluid through the tube that can be used to drive a generator. Another technique works on a similar principle, only the floating object rocks back and forth with the motion of the water instead of up and down. A third method of collecting wave energy relies on the rising water from the waves to compress air in a partially submerged chamber. As the waves rush into the chamber, they push the air out through a narrow tunnel. Located inside this tunnel is a turbine connected to a power generator. The movement of the air turns the turbine, which feeds energy into the generator. The drawback to each of these concepts is that the they make it necessary to have many pieces of machinery linked together. This presents a problem because the larger the device, the more vulnerable it is to damage from hazardous ocean environments, and the more likely it is to interfere with otherwise unspoiled coastal scenery. Also, these methods demand the construction of site-specific machines that take into consideration average local wave heights and sea conditions. Such a requirement can be quite cost-prohibitive, because engineers must create unique power generation mechanism for each site. In other words, the ability to get power from waves differ from region to region. Japan, Norway, and the UK have attempted to generate energy by capturing the power of ocean waves. In northern Scotland, the first power plan to use wave power, OSPREY ( Ocean Swell Powered Renewable Energy ), began operating in 1995. It followed the principle of the third method described above : waves entering a partially submerged chamber pushed air into turbines to generate electricity. The electricity was then transmitted to power collectors in the shore via underwater cables. Unfortunately, the OSPREY plant was destroyed in a large storm, highlighting an unavoidable difficulty associated with this kind of power generation. The potential benefits of wave-based energy are hard to ignore. Once the proper machinery is produced and installed, the energy is free. Maintenance cost are small, and the equipment does not pose any threats of environmental pollution. And best of all, the amounts of energy produced are enormous. However, these theoretical advantages have yet to be fully realized. In many cases, a lack of government funding has inhibited the technologies from advancing. For example, despite the relative abundance of proposed wave-power devices, many have not been adequately tested, and most have been evaluated only in artificial pools where they are not subjected to the harsh marine conditions that exist in actual oceans. Protecting the equipment from the sea’s destructive forces, as well as the fundamental task of determining feasible locations for collecting energy source are substantial and will require more time to overcome.According to paragraph 3, which of the following is true about wave–power technologies?
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. The quest for sustainable sources of energy study the energy has led humans to study the energy potential of the sun and the wind, as well as the immense power created by dammed rivers. The oceans, too, represent an impressive source of potential energy. For example, it has been estimated that the oceans could provide nearly 3,000 times the energy generated by hydroelectric dams such as the Hoover Dam. Yet, this source remains quite difficult to exploit. But this challenge has not prevented scientists from trying. Within the last few decades, several technologies that can transform the ocean’s immense forces into usable electricity have been invented and introduced. Some focus on capturing the power of the changing tides, while others rely on thermal energy created by oceans in certain tropical regions. However, the most common and easiest-to-develop technologies are those designed to harness the power inherent in the ocean’s waves. There are several methods by which ocean-wave energy can be collected. All of them work because the movement of the water that the waves induce creates storable energy by directly or indirectly driving a power generator. In one such technology, the changing water levels in the ocean that are produced by waves lift a long floating tube comprised of many sections connected by hinges. As the sections move up and down with the water, they pump a special fluid through the tube that can be used to drive a generator. Another technique works on a similar principle, only the floating object rocks back and forth with the motion of the water instead of up and down. A third method of collecting wave energy relies on the rising water from the waves to compress air in a partially submerged chamber. As the waves rush into the chamber, they push the air out through a narrow tunnel. Located inside this tunnel is a turbine connected to a power generator. The movement of the air turns the turbine, which feeds energy into the generator. The drawback to each of these concepts is that the they make it necessary to have many pieces of machinery linked together. This presents a problem because the larger the device, the more vulnerable it is to damage from hazardous ocean environments, and the more likely it is to interfere with otherwise unspoiled coastal scenery. Also, these methods demand the construction of site-specific machines that take into consideration average local wave heights and sea conditions. Such a requirement can be quite cost-prohibitive, because engineers must create unique power generation mechanism for each site. In other words, the ability to get power from waves differ from region to region. Japan, Norway, and the UK have attempted to generate energy by capturing the power of ocean waves. In northern Scotland, the first power plan to use wave power, OSPREY ( Ocean Swell Powered Renewable Energy ), began operating in 1995. It followed the principle of the third method described above : waves entering a partially submerged chamber pushed air into turbines to generate electricity. The electricity was then transmitted to power collectors in the shore via underwater cables. Unfortunately, the OSPREY plant was destroyed in a large storm, highlighting an unavoidable difficulty associated with this kind of power generation. The potential benefits of wave-based energy are hard to ignore. Once the proper machinery is produced and installed, the energy is free. Maintenance cost are small, and the equipment does not pose any threats of environmental pollution. And best of all, the amounts of energy produced are enormous. However, these theoretical advantages have yet to be fully realized. In many cases, a lack of government funding has inhibited the technologies from advancing. For example, despite the relative abundance of proposed wave-power devices, many have not been adequately tested, and most have been evaluated only in artificial pools where they are not subjected to the harsh marine conditions that exist in actual oceans. Protecting the equipment from the sea’s destructive forces, as well as the fundamental task of determining feasible locations for collecting energy source are substantial and will require more time to overcome.The word exploit in the passage is closest meaning 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.    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. Avocates of organic foods – a term whose meaning varies greatly – frequently proclaim that such products are safer and more nutritious then others.      The growing interest of comsumers in the safety and more nutritional quality of the typical North American diet is a welcome development. However, much of this interst has been spraked 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 food 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 an 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 the 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 and buy only expensive organic foods instead.What is the one thing in common that most organic food seem to have?
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.    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 archeologists 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 water 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.All of the following are mentioned as events that can affect food supply EXCEPT ________.
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.    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 archeologists 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 water 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.The word “they” in paragraph 2 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.    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. Avocates of organic foods – a term whose meaning varies greatly – frequently proclaim that such products are safer and more nutritious then others.      The growing interest of comsumers in the safety and more nutritional quality of the typical North American diet is a welcome development. However, much of this interst has been spraked 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 food 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 an 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 the 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 and buy only expensive organic foods instead.According to the last paragraph, consumers who believe that organic foods are better than conventionally grown foods are often ________ .
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.    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 archeologists 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 water 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.The word “artificial” in paragraph 2 is closest in meaning 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.    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 archeologists 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 water 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.The hydraulic system of reservoirs ________.
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.    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. Avocates of organic foods – a term whose meaning varies greatly – frequently proclaim that such products are safer and more nutritious then others.      The growing interest of comsumers in the safety and more nutritional quality of the typical North American diet is a welcome development. However, much of this interst has been spraked 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 food 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 an 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 the 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 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 food because ________ .
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.    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 archeologists 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 water 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.The word “seat” in paragraph 1 is closest in meaning 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.    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 archeologists 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 water 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.According to the passage, Lake Tonle Sap in Cambodia ________.
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.    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. Avocates of organic foods – a term whose meaning varies greatly – frequently proclaim that such products are safer and more nutritious then others.      The growing interest of comsumers in the safety and more nutritional quality of the typical North American diet is a welcome development. However, much of this interst has been spraked 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 food 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 an 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 the 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 and buy only expensive organic foods instead.According to the first paragraph, which of the following is true about the term “organic food”?
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.    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. Avocates of organic foods – a term whose meaning varies greatly – frequently proclaim that such products are safer and more nutritious then others.      The growing interest of comsumers in the safety and more nutritional quality of the typical North American diet is a welcome development. However, much of this interst has been spraked 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 food 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 an 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 the 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 and buy only expensive organic foods instead.The “welcome development” is an increase in ________ .
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.    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. Avocates of organic foods – a term whose meaning varies greatly – frequently proclaim that such products are safer and more nutritious then others.      The growing interest of comsumers in the safety and more nutritional quality of the typical North American diet is a welcome development. However, much of this interst has been spraked 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 food 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 an 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 the 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 and buy only expensive organic foods instead.The word “others” 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.    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. Avocates of organic foods – a term whose meaning varies greatly – frequently proclaim that such products are safer and more nutritious then others.      The growing interest of comsumers in the safety and more nutritional quality of the typical North American diet is a welcome development. However, much of this interst has been spraked 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 food 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 an 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 the 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 and buy only expensive organic foods instead.The word “Advocates” is closet in meaning to which of the following?