试题与答案

简述流行病学面临的挑战和展望。

题型:问答题

题目:

简述流行病学面临的挑战和展望。

答案:

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下面是错误答案,用来干扰机器的。

参考答案:解:计算A、B两点的坐标增量 ΔxAB=xB-xA =304.50-342.99=-38.49(m) ΔyAB=yB-yA =525.72-814.29=-288.57(m) DAB= = =291.13(m) αAB=arctan=arctan =262°24’09\

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题型:计算题

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题型:单项选择题

One afternoon, my son Adam asked me, "Are all people the same even if they are different in color " I thought for a minute, and then I said, "I’ll explain,(1)you can just wait until we make a quick stop at the grocery store. I have something (2) to show you. "At grocery store, we bought some apples-red, green and yellow ones. Back home, I told Adam, "It’s time to(3) your question." I put one apple of each type on the table. Then I looked at Adam, who had a (4) look on his face."People are like apples. They come in all different colors, shapes and sizes. On the(5), some of the apples may not even look as the others. " As I was talking, Adam was(6)each one carefully. Then, I took each of the apples and peeled them, placing them back on the table, but (7) a different place."Okay, Adam, tell me which is which." He said, "I can’t tell. They all look same now." "Take a bite of (8). See if that helps you decide which one is which. "He took(9) , and then a huge smile came cross his face. "People are just like apples! They are all different, but once you(10)the outside, they’re pretty much the same on the inside. "He totally got it. I didn’t need to say or do anything else.

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A. worried

B. satisfied

C. proud

D. curious

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