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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 Development of Refrigeration Cold storage, or refrigeration, is keeping food at temperatures between 32 and 45 degrees F in order to delay the growth of microorganisms - bacteria, molds, and yeast - that cause food to spoil. Refrigeration produces few changes in food, so meats, fish, eggs, milk, fruits, and vegetables keep their original flavor, color, and nutrition. Before artificial refrigeration was invented, people stored perishable food with ice or snow to lengthen its storage time. Preserving food by keeping it in an ice-filled pit is a 4,000-year-old art. Cold storage areas were built in basements, cellars, or caves, lined with wood or straw, and packed with ice. The ice was transported from mountains, or harvested from local lakes or rivers, and delivered in large blocks to homes and businesses. Artificial refrigeration is the process of removing heat from a substance, container, or enclosed area, to lower its temperature. The heat is moved from the inside of the container to the outside. A refrigerator uses the evaporation of a volatile liquid, or refrigerant, to absorb heat. In most types of refrigerators, the refrigerant is compressed, pumped through a pipe, and allowed to vaporize. As the liquid turns to vapor, it loses heat and gets colder because the molecules of vapor use energy to leave the liquid. The molecules left behind have less energy and so the liquid becomes colder. Thus, the air inside the refrigerator is chilled. Scientists and inventors from around the world developed artificial refrigeration during the eighteenth and nineteenth centuries. William Cullen demonstrated artificial refrigeration in Scotland in 1748, when he let ethyl ether boil into a partial vacuum. In 1805, American inventor Oliver Evans designed the first refrigeration machine that used vapor instead of liquid. In 1842, physician John Gorrie used Evans's design to create an air-cooling apparatus to treat yellow-fever patients in a Florida hospital. Gorrie later left his medical practice and experimented with ice making, and in 1851 he was granted the first U.S. patent for mechanical refrigeration. In the same year, an Australian printer, James Harrison, built an ether refrigerator after noticing that when he cleaned his type with ether it became very cold as the ether evaporated. Five years later, Harrison introduced vapor-compression refrigeration to the brewing and meatpacking industries. Brewing was the first industry in the United States to use mechanical refrigeration extensively, and in the 1870s, commercial refrigeration was primarily directed at breweries. German-born Adolphus Busch was the first to use artificial refrigeration at his brewery in St. Louis. Before refrigeration, brewers stored their beer in caves, and production was constrained by the amount of available cave space. Brewing was strictly a local business since beer was highly perishable and shipping it any distance would result in spoilage. Busch solved the storage problem with the commercial vapor- compression refrigerator. He solved the shipping problem with the newly invented refrigerated railcar, which was insulated with ice bunkers in each end. Air came in on the top, passed through the bunkers, and circulated through the car by gravity. In solving Busch's spoilage and storage problems, refrigeration also revolutionized an entire industry. By 1891, nearly every brewery was equipped with mechanical refrigerating machines. The refrigerators of today rely on the same basic principle of cooling caused by the rapid evaporation and expansion of gases. Until 1929, refrigerators used toxic gases - ammonia, methyl chloride, and sulfur dioxide - as refrigerants. After those gases accidentally killed several people, chlorofluorocarbons (CFCs) became the standard refrigerant. However, they were found to be harmful to the earth's ozone layer, so refrigerators now use a refrigerant called HFC 134a, which is less harmful to the ozone.Artificial refrigeration involves all of the following processes 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 Development of Refrigeration Cold storage, or refrigeration, is keeping food at temperatures between 32 and 45 degrees F in order to delay the growth of microorganisms - bacteria, molds, and yeast - that cause food to spoil. Refrigeration produces few changes in food, so meats, fish, eggs, milk, fruits, and vegetables keep their original flavor, color, and nutrition. Before artificial refrigeration was invented, people stored perishable food with ice or snow to lengthen its storage time. Preserving food by keeping it in an ice-filled pit is a 4,000-year-old art. Cold storage areas were built in basements, cellars, or caves, lined with wood or straw, and packed with ice. The ice was transported from mountains, or harvested from local lakes or rivers, and delivered in large blocks to homes and businesses. Artificial refrigeration is the process of removing heat from a substance, container, or enclosed area, to lower its temperature. The heat is moved from the inside of the container to the outside. A refrigerator uses the evaporation of a volatile liquid, or refrigerant, to absorb heat. In most types of refrigerators, the refrigerant is compressed, pumped through a pipe, and allowed to vaporize. As the liquid turns to vapor, it loses heat and gets colder because the molecules of vapor use energy to leave the liquid. The molecules left behind have less energy and so the liquid becomes colder. Thus, the air inside the refrigerator is chilled. Scientists and inventors from around the world developed artificial refrigeration during the eighteenth and nineteenth centuries. William Cullen demonstrated artificial refrigeration in Scotland in 1748, when he let ethyl ether boil into a partial vacuum. In 1805, American inventor Oliver Evans designed the first refrigeration machine that used vapor instead of liquid. In 1842, physician John Gorrie used Evans's design to create an air-cooling apparatus to treat yellow-fever patients in a Florida hospital. Gorrie later left his medical practice and experimented with ice making, and in 1851 he was granted the first U.S. patent for mechanical refrigeration. In the same year, an Australian printer, James Harrison, built an ether refrigerator after noticing that when he cleaned his type with ether it became very cold as the ether evaporated. Five years later, Harrison introduced vapor-compression refrigeration to the brewing and meatpacking industries. Brewing was the first industry in the United States to use mechanical refrigeration extensively, and in the 1870s, commercial refrigeration was primarily directed at breweries. German-born Adolphus Busch was the first to use artificial refrigeration at his brewery in St. Louis. Before refrigeration, brewers stored their beer in caves, and production was constrained by the amount of available cave space. Brewing was strictly a local business since beer was highly perishable and shipping it any distance would result in spoilage. Busch solved the storage problem with the commercial vapor- compression refrigerator. He solved the shipping problem with the newly invented refrigerated railcar, which was insulated with ice bunkers in each end. Air came in on the top, passed through the bunkers, and circulated through the car by gravity. In solving Busch's spoilage and storage problems, refrigeration also revolutionized an entire industry. By 1891, nearly every brewery was equipped with mechanical refrigerating machines. The refrigerators of today rely on the same basic principle of cooling caused by the rapid evaporation and expansion of gases. Until 1929, refrigerators used toxic gases - ammonia, methyl chloride, and sulfur dioxide - as refrigerants. After those gases accidentally killed several people, chlorofluorocarbons (CFCs) became the standard refrigerant. However, they were found to be harmful to the earth's ozone layer, so refrigerators now use a refrigerant called HFC 134a, which is less harmful to the ozone.What can be inferred from paragraph 1 about cold storage before the invention of artificial refrigeration?
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 Development of Refrigeration Cold storage, or refrigeration, is keeping food at temperatures between 32 and 45 degrees F in order to delay the growth of microorganisms - bacteria, molds, and yeast - that cause food to spoil. Refrigeration produces few changes in food, so meats, fish, eggs, milk, fruits, and vegetables keep their original flavor, color, and nutrition. Before artificial refrigeration was invented, people stored perishable food with ice or snow to lengthen its storage time. Preserving food by keeping it in an ice-filled pit is a 4,000-year-old art. Cold storage areas were built in basements, cellars, or caves, lined with wood or straw, and packed with ice. The ice was transported from mountains, or harvested from local lakes or rivers, and delivered in large blocks to homes and businesses. Artificial refrigeration is the process of removing heat from a substance, container, or enclosed area, to lower its temperature. The heat is moved from the inside of the container to the outside. A refrigerator uses the evaporation of a volatile liquid, or refrigerant, to absorb heat. In most types of refrigerators, the refrigerant is compressed, pumped through a pipe, and allowed to vaporize. As the liquid turns to vapor, it loses heat and gets colder because the molecules of vapor use energy to leave the liquid. The molecules left behind have less energy and so the liquid becomes colder. Thus, the air inside the refrigerator is chilled. Scientists and inventors from around the world developed artificial refrigeration during the eighteenth and nineteenth centuries. William Cullen demonstrated artificial refrigeration in Scotland in 1748, when he let ethyl ether boil into a partial vacuum. In 1805, American inventor Oliver Evans designed the first refrigeration machine that used vapor instead of liquid. In 1842, physician John Gorrie used Evans's design to create an air-cooling apparatus to treat yellow-fever patients in a Florida hospital. Gorrie later left his medical practice and experimented with ice making, and in 1851 he was granted the first U.S. patent for mechanical refrigeration. In the same year, an Australian printer, James Harrison, built an ether refrigerator after noticing that when he cleaned his type with ether it became very cold as the ether evaporated. Five years later, Harrison introduced vapor-compression refrigeration to the brewing and meatpacking industries. Brewing was the first industry in the United States to use mechanical refrigeration extensively, and in the 1870s, commercial refrigeration was primarily directed at breweries. German-born Adolphus Busch was the first to use artificial refrigeration at his brewery in St. Louis. Before refrigeration, brewers stored their beer in caves, and production was constrained by the amount of available cave space. Brewing was strictly a local business since beer was highly perishable and shipping it any distance would result in spoilage. Busch solved the storage problem with the commercial vapor- compression refrigerator. He solved the shipping problem with the newly invented refrigerated railcar, which was insulated with ice bunkers in each end. Air came in on the top, passed through the bunkers, and circulated through the car by gravity. In solving Busch's spoilage and storage problems, refrigeration also revolutionized an entire industry. By 1891, nearly every brewery was equipped with mechanical refrigerating machines. The refrigerators of today rely on the same basic principle of cooling caused by the rapid evaporation and expansion of gases. Until 1929, refrigerators used toxic gases - ammonia, methyl chloride, and sulfur dioxide - as refrigerants. After those gases accidentally killed several people, chlorofluorocarbons (CFCs) became the standard refrigerant. However, they were found to be harmful to the earth's ozone layer, so refrigerators now use a refrigerant called HFC 134a, which is less harmful to the ozone.The word “perishable” 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 Development of Refrigeration Cold storage, or refrigeration, is keeping food at temperatures between 32 and 45 degrees F in order to delay the growth of microorganisms - bacteria, molds, and yeast - that cause food to spoil. Refrigeration produces few changes in food, so meats, fish, eggs, milk, fruits, and vegetables keep their original flavor, color, and nutrition. Before artificial refrigeration was invented, people stored perishable food with ice or snow to lengthen its storage time. Preserving food by keeping it in an ice-filled pit is a 4,000-year-old art. Cold storage areas were built in basements, cellars, or caves, lined with wood or straw, and packed with ice. The ice was transported from mountains, or harvested from local lakes or rivers, and delivered in large blocks to homes and businesses. Artificial refrigeration is the process of removing heat from a substance, container, or enclosed area, to lower its temperature. The heat is moved from the inside of the container to the outside. A refrigerator uses the evaporation of a volatile liquid, or refrigerant, to absorb heat. In most types of refrigerators, the refrigerant is compressed, pumped through a pipe, and allowed to vaporize. As the liquid turns to vapor, it loses heat and gets colder because the molecules of vapor use energy to leave the liquid. The molecules left behind have less energy and so the liquid becomes colder. Thus, the air inside the refrigerator is chilled. Scientists and inventors from around the world developed artificial refrigeration during the eighteenth and nineteenth centuries. William Cullen demonstrated artificial refrigeration in Scotland in 1748, when he let ethyl ether boil into a partial vacuum. In 1805, American inventor Oliver Evans designed the first refrigeration machine that used vapor instead of liquid. In 1842, physician John Gorrie used Evans's design to create an air-cooling apparatus to treat yellow-fever patients in a Florida hospital. Gorrie later left his medical practice and experimented with ice making, and in 1851 he was granted the first U.S. patent for mechanical refrigeration. In the same year, an Australian printer, James Harrison, built an ether refrigerator after noticing that when he cleaned his type with ether it became very cold as the ether evaporated. Five years later, Harrison introduced vapor-compression refrigeration to the brewing and meatpacking industries. Brewing was the first industry in the United States to use mechanical refrigeration extensively, and in the 1870s, commercial refrigeration was primarily directed at breweries. German-born Adolphus Busch was the first to use artificial refrigeration at his brewery in St. Louis. Before refrigeration, brewers stored their beer in caves, and production was constrained by the amount of available cave space. Brewing was strictly a local business since beer was highly perishable and shipping it any distance would result in spoilage. Busch solved the storage problem with the commercial vapor- compression refrigerator. He solved the shipping problem with the newly invented refrigerated railcar, which was insulated with ice bunkers in each end. Air came in on the top, passed through the bunkers, and circulated through the car by gravity. In solving Busch's spoilage and storage problems, refrigeration also revolutionized an entire industry. By 1891, nearly every brewery was equipped with mechanical refrigerating machines. The refrigerators of today rely on the same basic principle of cooling caused by the rapid evaporation and expansion of gases. Until 1929, refrigerators used toxic gases - ammonia, methyl chloride, and sulfur dioxide - as refrigerants. After those gases accidentally killed several people, chlorofluorocarbons (CFCs) became the standard refrigerant. However, they were found to be harmful to the earth's ozone layer, so refrigerators now use a refrigerant called HFC 134a, which is less harmful to the ozone.What is the main reason that people developed methods of refrigeration?
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 development of genetically modified (GM) plants and animals had led to a huge global controversy. Opponents say that GM “Franken foods” are a threat to our well-being, and proponents say that the risks are minimal. There is one aspect of the war over GM that is often overlooked. Anyone who wears a cotton shirt these days is using a GM crop. Cotton is the only major non-food GM crop at present, but others are coming. GM cotton plants that is not food has not stopped the most passionate GM opponents from objecting. If GM cotton is grown in a field next to fields of non-GM cotton, they argue, then how to keep genes from being transferred from field to field. This danger, however, is not as compelling to the public as possible health hazards in food, so there is no great fury over GM cotton. GM cotton seeds produce higher yields, and they do without the need for pesticides. Planting of GM cotton has increased five fold since 1997; three-quarter of cotton in America, and over half in China, is now GM. Farmers like it because it increases their profits. Other options for non-food GM include new variety of flowers with different colors or scents, tougher grasses for lawns, and plants designed to soak up pollutants from the soil. The paper industry provides another example of potential for GM to help produce better and cheaper products. Paper is made from pulp, and pulp is generally made from trees. Researchers in New Zealand and Chile have been working on insect-resistant pines, and a Japanese firm has combined carrot genes with tree genes to make them grow better in poor soil. Another interesting case is that of tobacco. It is not food crop, but it is consumed, and GM tobacco plants with both more and less nicotine have been created. The tobacco plant, however, is an ideal target for GM, since its genetics are very well understood and it produces a lot of leaves. The value of the drugs that could be produced by GM tobacco is so high, many farmers could switch from growing tobacco for cigarettes to growing it for medicine. Since medical cost is rising, consumers would also be happy to use drugs produced in bulk by GM tobacco. The word “that” in paragraph 1 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 The development of genetically modified (GM) plants and animals had led to a huge global controversy. Opponents say that GM “Franken foods” are a threat to our well-being, and proponents say that the risks are minimal. There is one aspect of the war over GM that is often overlooked. Anyone who wears a cotton shirt these days is using a GM crop. Cotton is the only major non-food GM crop at present, but others are coming. GM cotton plants that is not food has not stopped the most passionate GM opponents from objecting. If GM cotton is grown in a field next to fields of non-GM cotton, they argue, then how to keep genes from being transferred from field to field. This danger, however, is not as compelling to the public as possible health hazards in food, so there is no great fury over GM cotton. GM cotton seeds produce higher yields, and they do without the need for pesticides. Planting of GM cotton has increased five fold since 1997; three-quarter of cotton in America, and over half in China, is now GM. Farmers like it because it increases their profits. Other options for non-food GM include new variety of flowers with different colors or scents, tougher grasses for lawns, and plants designed to soak up pollutants from the soil. The paper industry provides another example of potential for GM to help produce better and cheaper products. Paper is made from pulp, and pulp is generally made from trees. Researchers in New Zealand and Chile have been working on insect-resistant pines, and a Japanese firm has combined carrot genes with tree genes to make them grow better in poor soil. Another interesting case is that of tobacco. It is not food crop, but it is consumed, and GM tobacco plants with both more and less nicotine have been created. The tobacco plant, however, is an ideal target for GM, since its genetics are very well understood and it produces a lot of leaves. The value of the drugs that could be produced by GM tobacco is so high, many farmers could switch from growing tobacco for cigarettes to growing it for medicine. Since medical cost is rising, consumers would also be happy to use drugs produced in bulk by GM tobacco. What is the topic of the paragraph?