搜题请搜索小程序“爱下问搜题”
问题 选择题

能与H2在一定条件下发生加成反应，又能使酸性高锰酸钾溶液褪色的物质是

A．乙烯

B．苯

C．甲烷

D．乙醇

答案

答案：A

与氢气加成和使高锰酸钾褪色都是不饱和键的性质，故有乙烯。

补全对话，情景问答
从方框中选择最佳选项完成对话，有两项多余。
A. I like playing computer games.
B. Do you play computer games?
C. How do you do your homework on it?
D. They check my homework.
E. But I often chat with them at the weekend.
F. Yes, I do.
G. What games do you play?

Mike: Lucy, do you have a computer?
Lucy: __1__
Mike: What do you often do on it?
Lucy: I often visit websites and get some information for my homework.
Mike: __2__
Lucy: No, never. I think playing games wastes(浪费) too much time. What about you, Mike? Do you have a computer?
Mike: Yes. __3__ I think it's very interesting.
Lucy: Oh, I usually send emails to my teachers. __4__
Mike: Do you chat (聊天) with your friends on the Internet?
Lucy: Yes. __5__
1. _____  2. _____  3. _____  4. _____  5. _____
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多项选择题

大失血时尿少的原因是()

A．血容量减少引起抗利尿激素释放

B．血压显著降低引起肾血流量减少

C．肾素-血管紧张素-醛固酮系统激活

D．晶体渗透压升高引起抗利尿激素释放

E．肾血流量发生重新分布：髓质少皮质多
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