The great power of tornadoes is almost unbelievable. The speed of this whirling funnel shaped wind may be more than 500 miles pe

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问题     The great power of tornadoes is almost unbelievable. The speed of this whirling funnel shaped wind may be more than 500 miles per hour. It can tear up trees, carry buildings away, and can even lift large trucks off the highway. The tornado is like a giant vacuum sweeper that sucks up anything in its path. Experts believe that the most violent force of a tornado is found inside the funnel, where a vacuum is created because of very low air pressure. When this vacuum moves over a building which is filled with air under normal pressure, the difference between the air pressure inside the building and that outside causes the building to explode. The largest tornado on record had a funnel a mile wide.
    There are many interesting stories about the strange things that tornadoes have done in the U. S. Common wheat straw has been driven several inches into posts and trees. Buildings have been turned completely around on their foundations and have remained intact. People and animals have been carried hundreds of feet, often suffering no physical harm. Feathers have been removed from chickens. Cars, trucks, and even whole freight trains have been carried away.
    A tornado does not last long, about 20 to 30 minutes on the average. Usually it destroys an area about 16 miles long and the great damage that it does in one place last only about 30 seconds. Tornadoes normally occur on hot, humid days but not necessarily in the summer. The biggest and most destructive tornado in the U. S. struck on March 18,1925. Roaring along at a speed of 60 miles per hour, it swept clean a path a mile wide across the states of Missouri, Illinois, and Indian. In its 220 mile long journey across these three states, the tornado killed 689 people.
    More than 200 tornadoes strike in the United States every year. It is not possible to predict when a tornado will strike although the U. S. Weather Bureau gives storm warnings when conditions are right to cause a tornado. The safest place to be if a tornado seems likely is in some underground area such as a cellar or a basement.
The largest recorded tornado funnel was______ . (  )

选项 A、1 mile
B、6 miles
C、10 miles
D、18 mile

答案A

解析 细节题。“有记载的最大的台风是多少?”A选项“1英里”正确。文中第一段说The largest tornado on record had a funnel a mile wide。
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