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问题 单项选择题

电子显微镜的分辨能力可达

A．0.02gm
B．0.01gm
C．0.2nm
D．0.1nm
E．0.01nm

答案

参考答案：C

解析：电子显微镜利用电子源作为光源使物体成像，放大倍数可达数十万到百万倍，分辨率可达0.2nm。

完形填空

阅读下面短文，用所给动词的适当形式填空，使短文完整、通顺。每空不限一词。

Rose is one of the funniest girls in her class. She looks like a boy, and she is good at performing. So she 小题1:_________(choose) to play Harry Potter by her classmates last week. She said happily, “I’m sure that I am able to do the job well because I小题2:_____(see) the movie many times already.”

Dick, one of Rose’s best classmates, is also an actor in the play. He 小题3:_________(like) to perform the play with Rose. He said, “We are confident that we 小题4:________(do) well in our school art festival next week.”

Mrs. Smith, their teacher, pays much attention to their play. She often encourages them. Yesterday afternoon when she小题5:_________(watch) their performance, she took photos of them.

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单项选择题

我国成品油消费税实行( )的办法计算应纳税额。

A．从价定额
B．从量定额
C．累进
D．从价定额和从量定额
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