The state of Florida was once almost gobbled (大吃) up by snails(蜗牛). They were giant(巨大的) snails from Africa. A visitor took some to Florida, where they spread quickly. Some of the snails were as big as a person's hand. They ate the leaves on trees and other plants. They had to be stopped, and they were. Poison killed thousands of the snails, and Florida was saved.

　　Catching a snail should be easier than catching any other animal. The snail is the slowest of all land animals. Its top speed is 55 yards per hour. At this speed it would take the snail about 32 hours to travel one mile. A snail only goes that fast when it's very hungry.

　　The bar graph below shows some other top speeds.

　　A bar graph has bars of different lengths, instead of pictures. This kind of graph makes it easy to compare several things quickly. To read the graph, notice where each bar ends. Then find the closest number at the bottom of the graph.

　　Use the bar graph about running speeds to answer the questions.

1．What is the top speed of a rabbit?

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2．Fifty miles per hour is the top speed for ________ .

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3．What is the difference in running speed between a greyhound and a gazelle?

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4．The closest to an elephant in running speed is ________ .

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5．A rabbit and greyhound can both run faster than ________ .

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