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单选题 Steel containing even less than one percent of molybdenum is remarkably hard and useful for making fine cutting tools. Many molybdenum ores that contain less than 1 percent by mass of molybdenum are mined because the metal is rare and ______
学科：工程学科英语
时间：2023-06-11 16:39:57
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The shorter a pendulum is, the faster it swings. Most pendulum clocks have a setscrew by which one may adjust the length of the pendulum when the clock is not keeping accurate time. If the clock is running too fast, the pendulum is swing too fast and it should be ______A. lengthenedB. replacedC. shortenedD. stopped
题目2单选题
During the last half of the 19th century, the United States and Germany made rapid progress in industrialization. Their deposits of coal and iron — essential factors in developing industry — aided them in becoming ______A. self-sufficientB. manufacturing hubsC. democraciesD. cultural leaders
题目3单选题
Steel containing even less than one percent of molybdenum is remarkably hard and useful for making fine cutting tools. Many molybdenum ores that contain less than 1 percent by mass of molybdenum are mined because the metal is rare and ______A. valuableB. unavailableC. al alloyD. sharp
题目4单选题
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题目5单选题
Often, as soon as object is invented by one person, others quickly start making improvements and change in the object. Alexander Graham Bell invented the telephone, but so many changes have been made in it since it was invented that ______A. more people now can afford to have one in their homesB. we really cannot say that Bell invented itC. "telephone" is no longer a proper name for the instrumentD. one would scarcely recognize the original as being a telephone
题目6单选题
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题目7单选题
Disagreeable or too loud sounds can be so annoying to workers that their efficiency is reduced. Acoustical engineers have made many factories more pleasant to work in by the use of insulating materials that reduce noise. At the same time, the productivity of the workers is often ______A. musicalB. expensiveC. pleasantD. increased
题目8单选题
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题目9单选题
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题目10单选题
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