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问题 选择题

下列物质中含有氧分子的是（　　）

A．空气

B．二氧化锰

C．高锰酸钾

D．水

答案

A、氧分子构成氧气，空气中含有氧气，即含有氧分子；故A正确．

B、二氧化锰中含有氧元素，不含氧分子，故B错误；

C、KMnO4中含有氧元素，而无氧气分子，故C错误；

D、水中只含有水分子，不含氧分子，但含氧原子，故D错误．

故选：A．

阅读理解

读短文，选答案。

     Hello, my name is Amy. I get up at six forty. I have breakfast at 7:10. And then I go to school.  I have

four classes in the morning and two classes in the afternoon. I have lunch in the canteen at school. I go

home at four fifty. I have dinner at seven o'clock. I go to bed at nine thirty.

1. I get up at ________.         

A. 6:40          

B. 6:30

2. I have _____________ at 7:10.

A. lunch              

B. breakfast

3. I have _____________ classes today.

A. four              

B. six

4. I have lunch at______________.

A. school            

B. home          

5. I go to bed at______________.

A. seven o'clock    

B. nine thirty
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单项选择题

适宜加工辣根芥末的原料品种是______。

A．成熟的芥末籽

B．未成熟的芥末籽

C．辣味萝卜

D．山葵的根茎
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