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问题 单项选择题

的值为().

A.A

B.B

C.C

D.D

答案

参考答案：C

解析：

本题难度系数不大。分析题干可以得到，本题属于典型的分数运算，裂项相加型，每个分数的分母表示为2个数的乘积，且数字之差为1，所以：

原式，答案选择C选项。

阅读理解

I am a boy from the USA. Now I go to school in China. I have Chinese food now, I like it. I usually have porridge（粥）and milk for breakfast at home with my parents. Sometimes I have some small cakes, too. But I don’t have lunch at home. I have it at school with my classmates（同学）. I usually have meat or fish, rice and vegetables for lunch. After lunch I have some fruit. I get home at half past four in the afternoon. So I have supper with my parents again. Sometimes we go out for supper. My mother often cooks supper. Sometimes my sister does it. We usually have rice, fish, meat, vegetables and fruit juice for supper. We sometimes have noodles and dumplings. After supper, I often have some fruit. I like apples very much.

请根据短文内容，选择最佳答案。

小题1:Where is the boy from?

A．England.

B．China.

C．America.

D．Australia.小题2:The boy has breakfast with_______.

A．his classmates

B．his father and mother

C．his teachers

D．his brother and sister小题3:When does the boy usually get back home?

A．4:45

B．5.30

C．4:30

D．5:15小题4:How many people are there in the boy’s family？

A．Three

B．Four

C．Five

D．Six小题5:Where does the boy have lunch at weekends?

A．At home.

B．At school.

C．At home or at school..

D．We don’t know.
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推断题

A、B、C、D、E均为初中化学中不同类别的物质，它们的变化关系如图所示，其中红色物质A在一定条件 下可以转化为单质B，“—”表示相连的两种物质能发生反应。则：

(1)D的化学式为____。

(2)A转化为B的化学方程式____________________。

(3)C与E反应的化学方程式______________________。
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