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问题 单项选择题

在SQL语言中，删除视图的语句是( )。

A．ALTER VIEW

B．DROP VIEW

C．ZAP VIEW

D．DELETE VIEW

答案

参考答案：B

解析：[分析] 这个是一个概念题，删除视图的语句就是使用的DROP命令进行操作的。

阅读理解

I live with my grandmother in a Beijing yard house. One day last year, （1）我惊讶的看到一个外国人从我家隔壁的房子里出来. He was very tall with short brown hair and a pair of glasses. The first time I saw him, （2）I was too shy to speak to him. “My English is too bad！”I thought. My grandmother told me that he had just moved into our yard. “I don’t like it!” she said, "Foreigners aren't like us. Maybe he’ll play loud music and have parties every night! I' m sure he’s going to cause trouble."

Several days later, I met the foreigner as I was walking home after work. "Hello!" he said in Chinese! "My name's Tony. I've just moved into the house next door to yours. “While I was wondering what to say, he continued, "There's a nice bar down the road. Why don’t you and your family come to the bar and have dinner with me? “Bars are bad places," said my grandmother when I told her, but we decided to go. （3）The bar was not at all what I had expected. It was in a beautiful little yard house, with several large bookshelves and pictures of Tibet on the walls. Several Chinese people and foreigners were sitting drinking or reading books. I noticed that some of the foreigners were speaking reading books. I noticed that some of the foreigners were speaking place.

The bar served special "hutong pizzas". As we ate, Tony told us about himself—he is an English expert (专家) in environment. He always likes to be quiet. My grandmother said to me, “He really seems like a very nice young man.” Yes, Tony is my new neighbor, a nice foreigner.

阅读短文，按要求完成下面的任务。

小题1:把1处的汉语译为英语。

小题2:把2处改为同义句。

小题3:把3处的英语译为中文。

小题4:What did the writer’s grandmother think of Tony at first?

小题5:给短文拟一个标题。
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计算题

如图所示，一电荷量q=3×10-5C带正电的小球，用绝缘细线悬于竖直放置足够大的平行金属板中的O点。电键S合上后，当小球静止时，细线与竖直方向的夹角α=37°，已知两板相距d=0.1m，电源电动ε=1.5V，内阻r=0.5Ω，电阻R1=3Ω，R2=R3=R4=8Ω，g取10m/s2，已知sin37°=0.6，cos37°=0.8。求：

（1）电源的输出功率；

（2）两板间的电场强度的大小；

（3）带电小球的质量。

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