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问题 选择题

下列物质的用途利用物质其化学性质的是（　　）

A．氮气用于制氮肥

B．稀有气体用于霓虹灯

C．活性炭用于净化水

D．铜线用于制电缆

答案

A、氮肥属于氮的化合物，所以氮气用于制氮肥有新的物质生成了，属于化学性质，故A正确；

B、稀有气体用于霓虹灯是利用稀有气体冲入电后发出的光颜色不同，没有新的物质生成，属于物理性质，故B错；

C、活性炭用于净化水是利用活性炭的吸附性，没有新的物质生成，属于物理性质，故C错；

D、铜制电缆是利用铜的导电性，属于物理性质，故D错．

故选A．

阅读理解

阅读理解。

     This is my room.The books are in the bookcase.The picture of my family is on the wall.  My backpack

is on the chair. And I have a baseball. It's on the floor, between the bookcase and the desk. A computer is on the desk. Some CDs are behind(在……后面) the computer. And I have a cat. It's on my bed.

根据短文内容回答下列问题:

1.Does the writer(作者) have a room? 

                             

2.Where are the books?  

                             

3.Is the photo of the writer's family on the wall? 

                             

4. Does the writer have a sofa in his room?

                             

5.Where is the computer ?

                             
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解答题

（x-1）2-（x-1）（x+1）
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