题干

阅读:设试验结果落在某个区域S中每一点的机会均等,用A表示事件“试验结果落在S中的一个小区域M中”,那么事件A发生的概率P(A) =
M
S
.在桌面上放一张50 cm×50 cm的正方形白纸ABCD,⊙O是它的内切圆,小明随机地将1000粒大米撒到该白纸上,其中落在圆内的大米有800粒,由此可得圆周率 π 的值为(  )

A:3.1

B:3.2

C:3.14

D:3.15

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答案(点此获取答案解析)

B

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阅读下列短文,从每题所给的四个选项(A、B、C和D)中,选出最佳选项。
D
    I travel a lot, and I find out different “styles”(风格)of directions every time I ask “How can I get to the post office?”
    Foreign tourists are often confused(困惑)in Japan because most streets there don't have names; in Japan, people use landmarks(地标)in their directions instead of street names. For example, the Japanese will say to travelers, “Go straight down to the corner. Turn left at the big hotel and go past a fruit market. The post office is across from the bus stop.”
    In the countryside of the American Midwest, there are not usually many landmarks. There are no mountains, so the land is very flat; in many places there are no towns or buildings within miles. Instead of landmarks, people will tell you directions and distances. In Kansas or Iowa, for example, people will say, “Go north two miles. Turn east, and then go another mile.”
    People in Los Angeles, California, have no idea of distance on the map; they measure distance in time, not miles. “How far away is the post office?” you ask. “Oh,” they answer, “it is about five minutes from here.” You say, “Yes, but how many miles away is it?” They don't know.
    It's true that a person doesn't know the answer to your question sometimes. What happens in such a situation? A New Yorker might say, “Sorry, I have no idea.” But in Yucatan, Mexico, no one answers “I don't know.” People in Yucatan believe that “I don't know” is impolite. They usually give an answer, often a wrong one. A tourist can get very, very lost in Yucatan!