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问题 选择题

下列命名正确的是（　　）

A．2-乙基丙烷

B．2，5-二甲基-4-乙基己烷

C．2-甲基-3-异丙基戊烷

D．2，2-二甲基丙烷

答案

A、2-乙基丙烷，2-乙基，数目选取的主链不是最长的，最长碳链含有4个C，主链为丁烷，正确命名为：2-甲基丁烷，故A错误；

B、2，5-二甲基-4-乙基己烷，取代基编号之和不是最小的，取代基编号错误，正确命名应该为：2，5-二甲基-3-乙基己烷，故B错误；

C、2-甲基-3-异丙基戊烷，选取的主链没有满足-遇等长碳链时，支链最多为主链，正确命名为：2，4-二甲基-3-乙基戊烷，故C错误；

D、2，2-二甲基丙烷，满足烷烃的系统命名法，故D正确；

故选D．

完形填空

阅读下面短文，并借助上下文内容，在空格里填上一个合适的单词，使短文合理通顺。

One cool April 22 morning, people started the day as usual. Yet it was not a normal day. What’s so special about April 22? The answer is simple. It is Earth Day. People all 小题1:  the world celebrate this important day. The idea of having a special day to celebrate Earth began 小题2:    the 1960s. Life was very different then. Few people talked or even thought about the environment. Most people had no idea 小题3:   dirty our air and water were.

On April 22, 1970, twenty million Americans 小题4:   part in the first Earth Day activities. They showed that people really did want to do something about the environment. Since then many countries have passed 小题5:    to protect the air, water, land and animals.

The vehicles such as cars and buses must pass tests to make sure that they don’t cause too 小题6:     pollution. Thanks to the laws, cars today release (排放) about half as many bad chemicals as cars did in 1970. As a 小题7:  , the air is cleaner than it once was.

Rivers and lakes are also cleaner today than before. It’s a good thing. The Cuyahoga River in Ohio was so polluted 小题8:   rubbish and oil on the river even caught 小题9:   ! Today, the river is cleaner. It no longer burns. It’s healthy enough for birds, fish, and other animals.

Now the celebration has spread to other countries. More than 175 countries celebrate it each year. We should 小题10:   our best to help keep our planet healthy.
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单项选择题

下列关于行政监察控制腐败的属性，说法正确的是（）。

①行政监察机关是执行监察职能的专门机关

②行政监察的对象主要是行政机关及其公务员，也包括国家行政机关任命的、依法从事公务的其他人员

③行政监察的范围主要是行政机关、公务员的违法和违反行政纪律的行为

④行政监察的内容和手段是综合性的

A.①②③

B.①②④

C.①③④

D.①②③④
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