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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 from 35 to 42.         In the early 1800s, to reach the jump-off point for the West, a family from the East of the United States could either buy a steamboat passage to Missouri for themselves, their wagons and their livestock or, as happened more often, simply pile everything into a wagon, hitch up a team, and begin their overland trek right in their front yard.         Along the macadamized roads and turnpikes east of the Missouri River, travel was comparatively fast, camping easy, and supplies plentiful. Then, in one river town or another, the neophyte emigrants would pause to lay in provisions. For outfitting purposes, the town of Independence had been preeminent ever since 1827, but the rising momentum of pioneer emigration had produced some rival jump-off points. Westport and Fort Leavenworth flourished a few miles upriver. St. Joseph had sprung up 55 miles to the northwest; in fact, emigrants who went to Missouri by riverboat could save four days on the trail by staying on the paddle wheelers to St. Joe before striking overland.         At whatever jump-off point they chose, the emigrants studied guide books and directions, asked questions of others as green as themselves, and made their final decision about outfitting. They had various, sometimes conflicting, options. For example, either pack animals or two -wheel carts or wagons could be used for the overland crossing. A family man usually chose the wagon. It was the costliest and slowest of the three, but it provided space and shelter for children and for a wife who likely as not was pregnant. Everybody knew that a top-heavy covered wagon might blow over in a prairie wind or be overturned by mountain rocks, that it might mire in river mud or sink to its hubs in desert sand, but maybe if those things happened on this trip, they would happen to someone else. Anyway, most pioneers, with their farm background, were used to wagons. Which of the cities that served as a jump-off point can be inferred from the passage to be farthest west?
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 from 28 to 34.    Scientists do not yet thoroughly understand just how the body of an individual becomes sensitive to a substance that is harmless or even wholesome for the average person. Milk, wheat, and egg, for example, rank among the most healthful and widely used foods. Yet these foods can cause persons sensitive to them to suffer greatly. At first, the body of the individual is not harmed by coming into contact with the substance. After a varying interval of time, usually longer than a few weeks, the body becomes sensitive to it, and an allergy has begun to develop. Sometimes it’s hard to figure out if you have a food allergy, since it can show up so many different ways. Your symptoms could be caused by many other problems. You may have rashes, hives, joint pains mimicking arthritis, headaches, irritability, or depression. The most common food allergies are to milk, eggs, seafood, wheat, nuts, seeds, chocolate, oranges, and tomatoes. Many of these allergies will not develop if these foods are not fed to an infant until her or his intestines mature at around seven months. Breast milk also tends to be protective. Migraines can be set off by foods containing tyramine, phenathylamine, monosodium glutamate, or sodium nitrate. Common foods which contain these are chocolate, aged cheeses, sour cream, red wine, pickled herring, chicken livers, avocados, ripe bananas, cured meats, many Oriental and prepared foods (read the labels!). Some people have been successful in treating their migraines with supplements of B-vitamins, particularly B6 and niacin. Children who are hyperactive may benefit from eliminating food additives, especially colorings, and foods high in salicylates from their diets. The phrase “set off’ 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 from 28 to 34.    Scientists do not yet thoroughly understand just how the body of an individual becomes sensitive to a substance that is harmless or even wholesome for the average person. Milk, wheat, and egg, for example, rank among the most healthful and widely used foods. Yet these foods can cause persons sensitive to them to suffer greatly. At first, the body of the individual is not harmed by coming into contact with the substance. After a varying interval of time, usually longer than a few weeks, the body becomes sensitive to it, and an allergy has begun to develop. Sometimes it’s hard to figure out if you have a food allergy, since it can show up so many different ways. Your symptoms could be caused by many other problems. You may have rashes, hives, joint pains mimicking arthritis, headaches, irritability, or depression. The most common food allergies are to milk, eggs, seafood, wheat, nuts, seeds, chocolate, oranges, and tomatoes. Many of these allergies will not develop if these foods are not fed to an infant until her or his intestines mature at around seven months. Breast milk also tends to be protective. Migraines can be set off by foods containing tyramine, phenathylamine, monosodium glutamate, or sodium nitrate. Common foods which contain these are chocolate, aged cheeses, sour cream, red wine, pickled herring, chicken livers, avocados, ripe bananas, cured meats, many Oriental and prepared foods (read the labels!). Some people have been successful in treating their migraines with supplements of B-vitamins, particularly B6 and niacin. Children who are hyperactive may benefit from eliminating food additives, especially colorings, and foods high in salicylates from their diets. The word “symptoms” 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 from 35 to 42.         In the early 1800s, to reach the jump-off point for the West, a family from the East of the United States could either buy a steamboat passage to Missouri for themselves, their wagons and their livestock or, as happened more often, simply pile everything into a wagon, hitch up a team, and begin their overland trek right in their front yard.         Along the macadamized roads and turnpikes east of the Missouri River, travel was comparatively fast, camping easy, and supplies plentiful. Then, in one river town or another, the neophyte emigrants would pause to lay in provisions. For outfitting purposes, the town of Independence had been preeminent ever since 1827, but the rising momentum of pioneer emigration had produced some rival jump-off points. Westport and Fort Leavenworth flourished a few miles upriver. St. Joseph had sprung up 55 miles to the northwest; in fact, emigrants who went to Missouri by riverboat could save four days on the trail by staying on the paddle wheelers to St. Joe before striking overland.         At whatever jump-off point they chose, the emigrants studied guide books and directions, asked questions of others as green as themselves, and made their final decision about outfitting. They had various, sometimes conflicting, options. For example, either pack animals or two -wheel carts or wagons could be used for the overland crossing. A family man usually chose the wagon. It was the costliest and slowest of the three, but it provided space and shelter for children and for a wife who likely as not was pregnant. Everybody knew that a top-heavy covered wagon might blow over in a prairie wind or be overturned by mountain rocks, that it might mire in river mud or sink to its hubs in desert sand, but maybe if those things happened on this trip, they would happen to someone else. Anyway, most pioneers, with their farm background, were used to wagons. The word “preeminent” 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 from 28 to 34.         During the second half of the nineteenth century, the production of food and feed crops in the United States rose at an extraordinarily rapid rate. Com production increased by four and a half times, hay by five times, oats and wheat by seven times. The most crucial factor behind this phenomenal upsurge in productivity was the widespread adoption of labor-saving machinery by northern farmers. By 1850 horse-drawn reaping machines that cut grain were being introduced into the major grain-growing regions of the country. Horse-powered threshing machines to separate the seeds from the plants were already in general use. However, it was the onset of the Civil War in 1861 that provided the great stimulus for the mechanization of northern agriculture. With much of the labor force inducted into the army and with grain prices on the rise, northern farmers rushed to avail themselves of the new labor-saving equipment. In 1860 there were approximately 80,000 reapers in the country; five years later there were 350,000.         After the close of the war in 1865, machinery became ever more important in northern agriculture, and improved equipment was continually introduced. By 1880 a self-binding reaper had been perfected that not only cut the grain, but also gathered the stalks and bound them with twine. Threshing machines were also being improved and enlarged, and after 1870 they were increasingly powered by steam engines rather than by horses. Since steam-powered threshing machines were costly items-running from $ 1,000 to $4,000 - they were usually owned by custom thresher owners who then worked their way from farm to farm during the harvest season. “Combines” were also coming into use on the great wheat ranches in California and the Pacific Northwest. These ponderous machines - sometimes pulled by as many as 40 horses - reaped the grain, threshed it, and bagged it, all in one simultaneous operation.           The adoption of labor-saving machinery had a profound effect upon the sale of agricultural operations in the northern states-allowing farmers to increase vastly their crop acreage. By the end of century, a farmer employing the new machinery could plant and harvest two and half times as much com as a farmer had using hand methods 50 years before. It can be inferred from the passage that most fanners did not own threshing machines 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 from 28 to 34.    Scientists do not yet thoroughly understand just how the body of an individual becomes sensitive to a substance that is harmless or even wholesome for the average person. Milk, wheat, and egg, for example, rank among the most healthful and widely used foods. Yet these foods can cause persons sensitive to them to suffer greatly. At first, the body of the individual is not harmed by coming into contact with the substance. After a varying interval of time, usually longer than a few weeks, the body becomes sensitive to it, and an allergy has begun to develop. Sometimes it’s hard to figure out if you have a food allergy, since it can show up so many different ways. Your symptoms could be caused by many other problems. You may have rashes, hives, joint pains mimicking arthritis, headaches, irritability, or depression. The most common food allergies are to milk, eggs, seafood, wheat, nuts, seeds, chocolate, oranges, and tomatoes. Many of these allergies will not develop if these foods are not fed to an infant until her or his intestines mature at around seven months. Breast milk also tends to be protective. Migraines can be set off by foods containing tyramine, phenathylamine, monosodium glutamate, or sodium nitrate. Common foods which contain these are chocolate, aged cheeses, sour cream, red wine, pickled herring, chicken livers, avocados, ripe bananas, cured meats, many Oriental and prepared foods (read the labels!). Some people have been successful in treating their migraines with supplements of B-vitamins, particularly B6 and niacin. Children who are hyperactive may benefit from eliminating food additives, especially colorings, and foods high in salicylates from their diets. The topic of this passage is _____________ 
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 from 28 to 34.         During the second half of the nineteenth century, the production of food and feed crops in the United States rose at an extraordinarily rapid rate. Com production increased by four and a half times, hay by five times, oats and wheat by seven times. The most crucial factor behind this phenomenal upsurge in productivity was the widespread adoption of labor-saving machinery by northern farmers. By 1850 horse-drawn reaping machines that cut grain were being introduced into the major grain-growing regions of the country. Horse-powered threshing machines to separate the seeds from the plants were already in general use. However, it was the onset of the Civil War in 1861 that provided the great stimulus for the mechanization of northern agriculture. With much of the labor force inducted into the army and with grain prices on the rise, northern farmers rushed to avail themselves of the new labor-saving equipment. In 1860 there were approximately 80,000 reapers in the country; five years later there were 350,000.         After the close of the war in 1865, machinery became ever more important in northern agriculture, and improved equipment was continually introduced. By 1880 a self-binding reaper had been perfected that not only cut the grain, but also gathered the stalks and bound them with twine. Threshing machines were also being improved and enlarged, and after 1870 they were increasingly powered by steam engines rather than by horses. Since steam-powered threshing machines were costly items-running from $ 1,000 to $4,000 - they were usually owned by custom thresher owners who then worked their way from farm to farm during the harvest season. “Combines” were also coming into use on the great wheat ranches in California and the Pacific Northwest. These ponderous machines - sometimes pulled by as many as 40 horses - reaped the grain, threshed it, and bagged it, all in one simultaneous operation.           The adoption of labor-saving machinery had a profound effect upon the sale of agricultural operations in the northern states-allowing farmers to increase vastly their crop acreage. By the end of century, a farmer employing the new machinery could plant and harvest two and half times as much com as a farmer had using hand methods 50 years before. 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 from 43 to 50.   Working on the computer is very tough on your body, which is not used to this modem type of work. Sitting has long been known to cause back pain and negatively influence circulation, which can promote cardiovascular disease. Extensive use of the keyboard and mouse can lead to stiffening of the muscles in your hands, arms, and neck. Staring at a bright screen for too long can cause dry eyes and headaches. So, computer work can be as unhealthy a job as you can imagine.   First and foremost, sitting for long stretches of time is a very serious health risk! Sitting affects your blood circulation, your back experiences a steady stress, you are more likely to drink and eat stuff that isn’t good for you, and you bum very little calories, making it more likely that you overeat. As a result, sitting contributes to a host of conditions, most notably gaining weight, diabetes, heart disease, cancer, and consequently a shortened life span.   Second, bad posture causes pain. You can develop bad posture from anything you do habitually, whether it’s sitting, standing, or walking. The typical consequences associated with bad posture while working on the computer are pain in the back, shoulder, and neck, often resulting in tension headaches.   Third, staring at the screen causes eve strain. Staring at a bright screen for hours can lead to eye fatigue or eye strain, headaches, blurred vision, burning, itching or tearing eyes, and temporary vision disorders. Fortunately, eye strain rarely results in a permanent condition and symptoms can be prevented or cured rather easily.   Last, but not least, emotional pressure and isolation cause anxiety and depression. Computers are very efficient tools in that they help us with getting more work done in less time. At the same time, you spend less face-to-face time with your colleagues, family, or friends. This can lead to isolation, anxiety, and depression, i.e. both physical and mental health issues. The symptoms are manifold and can include tense muscles, back pain, headaches, poor sleep (insomnia), increased or flat breathing, quickened pulse, and generally signs of stress, depression, or anxiety.   (Adaptedfrom: http://www.makeuseof.com/tag/5-reasons-working-with-compiiters-is-bad-for-you-how-to-stay-healthy/)  What is the organization of the passage?    
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 from 28 to 34.         During the second half of the nineteenth century, the production of food and feed crops in the United States rose at an extraordinarily rapid rate. Com production increased by four and a half times, hay by five times, oats and wheat by seven times. The most crucial factor behind this phenomenal upsurge in productivity was the widespread adoption of labor-saving machinery by northern farmers. By 1850 horse-drawn reaping machines that cut grain were being introduced into the major grain-growing regions of the country. Horse-powered threshing machines to separate the seeds from the plants were already in general use. However, it was the onset of the Civil War in 1861 that provided the great stimulus for the mechanization of northern agriculture. With much of the labor force inducted into the army and with grain prices on the rise, northern farmers rushed to avail themselves of the new labor-saving equipment. In 1860 there were approximately 80,000 reapers in the country; five years later there were 350,000.         After the close of the war in 1865, machinery became ever more important in northern agriculture, and improved equipment was continually introduced. By 1880 a self-binding reaper had been perfected that not only cut the grain, but also gathered the stalks and bound them with twine. Threshing machines were also being improved and enlarged, and after 1870 they were increasingly powered by steam engines rather than by horses. Since steam-powered threshing machines were costly items-running from $ 1,000 to $4,000 - they were usually owned by custom thresher owners who then worked their way from farm to farm during the harvest season. “Combines” were also coming into use on the great wheat ranches in California and the Pacific Northwest. These ponderous machines - sometimes pulled by as many as 40 horses - reaped the grain, threshed it, and bagged it, all in one simultaneous operation.           The adoption of labor-saving machinery had a profound effect upon the sale of agricultural operations in the northern states-allowing farmers to increase vastly their crop acreage. By the end of century, a farmer employing the new machinery could plant and harvest two and half times as much com as a farmer had using hand methods 50 years before. Combines and self-binding reapers were similar because each _________.
* 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 from 43 to 50.   Working on the computer is very tough on your body, which is not used to this modem type of work. Sitting has long been known to cause back pain and negatively influence circulation, which can promote cardiovascular disease. Extensive use of the keyboard and mouse can lead to stiffening of the muscles in your hands, arms, and neck. Staring at a bright screen for too long can cause dry eyes and headaches. So, computer work can be as unhealthy a job as you can imagine.   First and foremost, sitting for long stretches of time is a very serious health risk! Sitting affects your blood circulation, your back experiences a steady stress, you are more likely to drink and eat stuff that isn’t good for you, and you bum very little calories, making it more likely that you overeat. As a result, sitting contributes to a host of conditions, most notably gaining weight, diabetes, heart disease, cancer, and consequently a shortened life span.   Second, bad posture causes pain. You can develop bad posture from anything you do habitually, whether it’s sitting, standing, or walking. The typical consequences associated with bad posture while working on the computer are pain in the back, shoulder, and neck, often resulting in tension headaches.   Third, staring at the screen causes eve strain. Staring at a bright screen for hours can lead to eye fatigue or eye strain, headaches, blurred vision, burning, itching or tearing eyes, and temporary vision disorders. Fortunately, eye strain rarely results in a permanent condition and symptoms can be prevented or cured rather easily.   Last, but not least, emotional pressure and isolation cause anxiety and depression. Computers are very efficient tools in that they help us with getting more work done in less time. At the same time, you spend less face-to-face time with your colleagues, family, or friends. This can lead to isolation, anxiety, and depression, i.e. both physical and mental health issues. The symptoms are manifold and can include tense muscles, back pain, headaches, poor sleep (insomnia), increased or flat breathing, quickened pulse, and generally signs of stress, depression, or anxiety.   (Adaptedfrom: http://www.makeuseof.com/tag/5-reasons-working-with-compiiters-is-bad-for-you-how-to-stay-healthy/)  According to the passage, all the mentioned issues are________.    
* 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 from 43 to 50.   Working on the computer is very tough on your body, which is not used to this modem type of work. Sitting has long been known to cause back pain and negatively influence circulation, which can promote cardiovascular disease. Extensive use of the keyboard and mouse can lead to stiffening of the muscles in your hands, arms, and neck. Staring at a bright screen for too long can cause dry eyes and headaches. So, computer work can be as unhealthy a job as you can imagine.   First and foremost, sitting for long stretches of time is a very serious health risk! Sitting affects your blood circulation, your back experiences a steady stress, you are more likely to drink and eat stuff that isn’t good for you, and you bum very little calories, making it more likely that you overeat. As a result, sitting contributes to a host of conditions, most notably gaining weight, diabetes, heart disease, cancer, and consequently a shortened life span.   Second, bad posture causes pain. You can develop bad posture from anything you do habitually, whether it’s sitting, standing, or walking. The typical consequences associated with bad posture while working on the computer are pain in the back, shoulder, and neck, often resulting in tension headaches.   Third, staring at the screen causes eve strain. Staring at a bright screen for hours can lead to eye fatigue or eye strain, headaches, blurred vision, burning, itching or tearing eyes, and temporary vision disorders. Fortunately, eye strain rarely results in a permanent condition and symptoms can be prevented or cured rather easily.   Last, but not least, emotional pressure and isolation cause anxiety and depression. Computers are very efficient tools in that they help us with getting more work done in less time. At the same time, you spend less face-to-face time with your colleagues, family, or friends. This can lead to isolation, anxiety, and depression, i.e. both physical and mental health issues. The symptoms are manifold and can include tense muscles, back pain, headaches, poor sleep (insomnia), increased or flat breathing, quickened pulse, and generally signs of stress, depression, or anxiety.   (Adaptedfrom: http://www.makeuseof.com/tag/5-reasons-working-with-compiiters-is-bad-for-you-how-to-stay-healthy/)  It can be inferred from the passage that emotional and physical issues are________.    
* 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 from 43 to 50.   Working on the computer is very tough on your body, which is not used to this modem type of work. Sitting has long been known to cause back pain and negatively influence circulation, which can promote cardiovascular disease. Extensive use of the keyboard and mouse can lead to stiffening of the muscles in your hands, arms, and neck. Staring at a bright screen for too long can cause dry eyes and headaches. So, computer work can be as unhealthy a job as you can imagine.   First and foremost, sitting for long stretches of time is a very serious health risk! Sitting affects your blood circulation, your back experiences a steady stress, you are more likely to drink and eat stuff that isn’t good for you, and you bum very little calories, making it more likely that you overeat. As a result, sitting contributes to a host of conditions, most notably gaining weight, diabetes, heart disease, cancer, and consequently a shortened life span.   Second, bad posture causes pain. You can develop bad posture from anything you do habitually, whether it’s sitting, standing, or walking. The typical consequences associated with bad posture while working on the computer are pain in the back, shoulder, and neck, often resulting in tension headaches.   Third, staring at the screen causes eve strain. Staring at a bright screen for hours can lead to eye fatigue or eye strain, headaches, blurred vision, burning, itching or tearing eyes, and temporary vision disorders. Fortunately, eye strain rarely results in a permanent condition and symptoms can be prevented or cured rather easily.   Last, but not least, emotional pressure and isolation cause anxiety and depression. Computers are very efficient tools in that they help us with getting more work done in less time. At the same time, you spend less face-to-face time with your colleagues, family, or friends. This can lead to isolation, anxiety, and depression, i.e. both physical and mental health issues. The symptoms are manifold and can include tense muscles, back pain, headaches, poor sleep (insomnia), increased or flat breathing, quickened pulse, and generally signs of stress, depression, or anxiety.   (Adaptedfrom: http://www.makeuseof.com/tag/5-reasons-working-with-compiiters-is-bad-for-you-how-to-stay-healthy/)  Which of the followings can best replace the word “eye strain” in Paragraph 4?     
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 from 28 to 34.         During the second half of the nineteenth century, the production of food and feed crops in the United States rose at an extraordinarily rapid rate. Com production increased by four and a half times, hay by five times, oats and wheat by seven times. The most crucial factor behind this phenomenal upsurge in productivity was the widespread adoption of labor-saving machinery by northern farmers. By 1850 horse-drawn reaping machines that cut grain were being introduced into the major grain-growing regions of the country. Horse-powered threshing machines to separate the seeds from the plants were already in general use. However, it was the onset of the Civil War in 1861 that provided the great stimulus for the mechanization of northern agriculture. With much of the labor force inducted into the army and with grain prices on the rise, northern farmers rushed to avail themselves of the new labor-saving equipment. In 1860 there were approximately 80,000 reapers in the country; five years later there were 350,000.         After the close of the war in 1865, machinery became ever more important in northern agriculture, and improved equipment was continually introduced. By 1880 a self-binding reaper had been perfected that not only cut the grain, but also gathered the stalks and bound them with twine. Threshing machines were also being improved and enlarged, and after 1870 they were increasingly powered by steam engines rather than by horses. Since steam-powered threshing machines were costly items-running from $ 1,000 to $4,000 - they were usually owned by custom thresher owners who then worked their way from farm to farm during the harvest season. “Combines” were also coming into use on the great wheat ranches in California and the Pacific Northwest. These ponderous machines - sometimes pulled by as many as 40 horses - reaped the grain, threshed it, and bagged it, all in one simultaneous operation.           The adoption of labor-saving machinery had a profound effect upon the sale of agricultural operations in the northern states-allowing farmers to increase vastly their crop acreage. By the end of century, a farmer employing the new machinery could plant and harvest two and half times as much com as a farmer had using hand methods 50 years before. According to the passage, why was the Civil War a stimulus for mechanization?
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 from 28 to 34.         During the second half of the nineteenth century, the production of food and feed crops in the United States rose at an extraordinarily rapid rate. Com production increased by four and a half times, hay by five times, oats and wheat by seven times. The most crucial factor behind this phenomenal upsurge in productivity was the widespread adoption of labor-saving machinery by northern farmers. By 1850 horse-drawn reaping machines that cut grain were being introduced into the major grain-growing regions of the country. Horse-powered threshing machines to separate the seeds from the plants were already in general use. However, it was the onset of the Civil War in 1861 that provided the great stimulus for the mechanization of northern agriculture. With much of the labor force inducted into the army and with grain prices on the rise, northern farmers rushed to avail themselves of the new labor-saving equipment. In 1860 there were approximately 80,000 reapers in the country; five years later there were 350,000.         After the close of the war in 1865, machinery became ever more important in northern agriculture, and improved equipment was continually introduced. By 1880 a self-binding reaper had been perfected that not only cut the grain, but also gathered the stalks and bound them with twine. Threshing machines were also being improved and enlarged, and after 1870 they were increasingly powered by steam engines rather than by horses. Since steam-powered threshing machines were costly items-running from $ 1,000 to $4,000 - they were usually owned by custom thresher owners who then worked their way from farm to farm during the harvest season. “Combines” were also coming into use on the great wheat ranches in California and the Pacific Northwest. These ponderous machines - sometimes pulled by as many as 40 horses - reaped the grain, threshed it, and bagged it, all in one simultaneous operation.           The adoption of labor-saving machinery had a profound effect upon the sale of agricultural operations in the northern states-allowing farmers to increase vastly their crop acreage. By the end of century, a farmer employing the new machinery could plant and harvest two and half times as much com as a farmer had using hand methods 50 years before. The phrase “avail themselves of” 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 from 28 to 34.         During the second half of the nineteenth century, the production of food and feed crops in the United States rose at an extraordinarily rapid rate. Com production increased by four and a half times, hay by five times, oats and wheat by seven times. The most crucial factor behind this phenomenal upsurge in productivity was the widespread adoption of labor-saving machinery by northern farmers. By 1850 horse-drawn reaping machines that cut grain were being introduced into the major grain-growing regions of the country. Horse-powered threshing machines to separate the seeds from the plants were already in general use. However, it was the onset of the Civil War in 1861 that provided the great stimulus for the mechanization of northern agriculture. With much of the labor force inducted into the army and with grain prices on the rise, northern farmers rushed to avail themselves of the new labor-saving equipment. In 1860 there were approximately 80,000 reapers in the country; five years later there were 350,000.         After the close of the war in 1865, machinery became ever more important in northern agriculture, and improved equipment was continually introduced. By 1880 a self-binding reaper had been perfected that not only cut the grain, but also gathered the stalks and bound them with twine. Threshing machines were also being improved and enlarged, and after 1870 they were increasingly powered by steam engines rather than by horses. Since steam-powered threshing machines were costly items-running from $ 1,000 to $4,000 - they were usually owned by custom thresher owners who then worked their way from farm to farm during the harvest season. “Combines” were also coming into use on the great wheat ranches in California and the Pacific Northwest. These ponderous machines - sometimes pulled by as many as 40 horses - reaped the grain, threshed it, and bagged it, all in one simultaneous operation.           The adoption of labor-saving machinery had a profound effect upon the sale of agricultural operations in the northern states-allowing farmers to increase vastly their crop acreage. By the end of century, a farmer employing the new machinery could plant and harvest two and half times as much com as a farmer had using hand methods 50 years before. The word “crucial” 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 from 28 to 34.         During the second half of the nineteenth century, the production of food and feed crops in the United States rose at an extraordinarily rapid rate. Com production increased by four and a half times, hay by five times, oats and wheat by seven times. The most crucial factor behind this phenomenal upsurge in productivity was the widespread adoption of labor-saving machinery by northern farmers. By 1850 horse-drawn reaping machines that cut grain were being introduced into the major grain-growing regions of the country. Horse-powered threshing machines to separate the seeds from the plants were already in general use. However, it was the onset of the Civil War in 1861 that provided the great stimulus for the mechanization of northern agriculture. With much of the labor force inducted into the army and with grain prices on the rise, northern farmers rushed to avail themselves of the new labor-saving equipment. In 1860 there were approximately 80,000 reapers in the country; five years later there were 350,000.         After the close of the war in 1865, machinery became ever more important in northern agriculture, and improved equipment was continually introduced. By 1880 a self-binding reaper had been perfected that not only cut the grain, but also gathered the stalks and bound them with twine. Threshing machines were also being improved and enlarged, and after 1870 they were increasingly powered by steam engines rather than by horses. Since steam-powered threshing machines were costly items-running from $ 1,000 to $4,000 - they were usually owned by custom thresher owners who then worked their way from farm to farm during the harvest season. “Combines” were also coming into use on the great wheat ranches in California and the Pacific Northwest. These ponderous machines - sometimes pulled by as many as 40 horses - reaped the grain, threshed it, and bagged it, all in one simultaneous operation.            The adoption of labor-saving machinery had a profound effect upon the sale of agricultural operations in the northern states-allowing farmers to increase vastly their crop acreage. By the end of century, a farmer employing the new machinery could plant and harvest two and half times as much com as a farmer had using hand methods 50 years before. What aspect of farming in the United States in the nineteenth century does the passage mainly discuss?