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问题 问答题

在测定滑轮组的机械效率的实验中，采用如图所示的安装方法，则滑轮组由______段绳子吊着物体．

答案

由图知：绳子的始端固定在动滑轮上，然后绕过定滑轮和动滑轮，所以承担物重的绳子是3段．

故答案为：3．

完形填空

Thirty-two people watched Kitty Genovese   1          (kill) right below their windows. She was   2             neighbor. Yet   3           of the 32 helped her. Not one even called the police.

John Barley and Bib Fatane went beyond the headlines to research into the     reasons  4        people didn’t act. They found that a person has to go through two steps  5       he can help. First he has to notice that it is      6       emergency(紧急情况). Is the smoke coming into the room  7      a leak in the air conditioning? Is it “steam pipes”? Or is it really smoke from a fire? It’s not always easy to tell if you are faced with a real emergency. Second, and   8      important, the person faced with an emergency must feel personally   9      (responsibility). He must feel that he must help,   10     the person won’t get the help he needs.

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填空题

Visual Studio 2008是第一个允许开发人员针对______多个版本开发的Visual Studio版本。
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