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问题 填空题

(6分) (6分)汽油不仅是最重要的燃料，而且是重要的化工原料，它既可以裂解得到气态化工原料如乙烯等，还可以在催化剂催化下改变分子结构，由链烃变成芳香烃，如已烷变成苯，庚烷变成甲苯，这个变化叫异构化。请根据以汽油为原料的下列衍变关系，写出相应的化学方程式(有机物写结构简式)，在括弧中填反应类型。

（1）______________________________________（2）_______________________________

（3）_____________________________________（4）_______________________________。

答案

加成反应    加聚反应   加成反应   硝化反应

(2) nCH2=CHCH→[CH2-CH(CH3)]n

完形填空

短文填空  根据短文内容及首字母提示,补全空格内单词，使短文完整、通顺（共10题；每小

题1分，满分10分）

Many people say dolphins are very intelligent(聪颖的). They seem to be able to think, understand, and learn things quickly. But are they as c  小题1:   as humans or more like cats or dogs? Scientists say dolphins’ intelligence is s 小题2:   to human intelligence in some ways.

How? Like h  小题3: , every dolphin has a “name”. It is a special whistle. Scientists think dolphins, like people, “t 小题4:  ” to each other about a lot of things, such as their age, their feelings, or finding food. And , like humans, dolphins use a system(系统) of sounds and body l 小题5:   to communicate. But understanding their conversation is not easy for human. No one “speaks dolphin” yet, but some scientists are trying to learn.

Dolphins are also social animals. They live in groups, and they often come to play games from different groups and have f 小题6:  , just like people. In fact, playing t 小题7:  is something only intelligent animals do.

Dolphins and humans b 小题8:   make plans to get something they want. In the seas of southern Brazil, dolphins use an interesting way to get food. When fish are n 小题9:  a boat, dolphins signal (发信号) to the fishermen to put their nets(网) in the water. And the men can catch a lot of fish. What is advantage for the dolphins? Why do they h 小题10:  the men? The dolphins can get some of the fish.
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单项选择题

已知某个国家的预算是平衡的，国民收入还未达到充分就业的水平。在政府支出和税率不变的条件下，如果私人投资增加，那么国民收入形成新的均衡的时候()。

A.政府财政收支平衡

B.出现财政赤字

C.出现财政盈余

D.以上都不对
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