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问题 多项选择题

微波/被动红外双鉴探测器中什么探测技术并存（）？

A.红外

B.被动红外

C.微波

D.磁开关

答案

参考答案：B, C

完形填空
完形填空。
     A good dictionary is __1__ important tool. It will tell you __2__ only what a word means but how it
 uses . A dictionary needs to be printed again about every ten years. Languages develop and a good
  dictionary must __3__ these new changes. A new English dictionary will only tell you __4__ most people
  use the language today. It will not tell you what is right __5__ wrong. It may tell you the right time to use
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  Your dictionary also has a lot of other interesting facts in it. After you have learned to use a dictionary , it
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选择题

抽制细线时可用激光监控其粗细，如图所示，激光束越过细丝时产生的条纹和它通过遮光板上的一条同样宽度的窄缝规律相同，则

A．这是利用光的衍射现象B．这是利用光的干涉现象
C．如果屏上条纹变宽，表明抽制的丝细了
D．如果屏上条纹变宽，表明抽丝的丝粗了
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