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问题 单项选择题

下列关于大气的正确叙述是（）。

A、几乎全部的水汽、尘埃、氮、氧都集中在对流层。

B、干洁空气的主要成分是氮、氧和二氧化碳。

C、臭氧主要集中在平流层大气中。

D、臭氧能吸收波长小于0.175mm的太阳紫外线，保护地球上的生命。

答案

参考答案：C

阅读理解
阅读理解.

    Ai Fukuhara (福原爱),the Japanese table tennis star, was born on Nov.11, 1988. She started playing
ping-pong when she was three. At that time, she was too small. She couldn't see over the tabletop (桌面). She had to stand on boxes to play against adults (成人) in exhibition (展览) matches.
    Now she is a very famous player. But she still works very hard and she practices for five hours a day
during the week after morning school lessons and eight hours a day at the weekend.
    In May 2003, Fukuhara made the quarterfinals  (四分之一决赛)  of the World  Championships.
    At the age of 15, she was the youngest player for Japan at the 2004 Olympic Games. She joined the
Liaoning Club in 2005."I hope I can l earn from my  Chinese teammates and  improve (改善) my
preparation for the 2008 Olympics."said Ai Fukuhara.

 Name
Ai Fukuhara
Birthday
Nov.11, 1988
Nationality
1._______
Job
ping-pong player
 Career
joined 2.___________________ in 2003
joined 3.___________________ in 2004
joined 4.___________________ in 2005
Words or phrases to describe her
5. ___________________
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单项选择题

图纸的标题栏内不应有（）。

A、工程名称

B、图号、图名

C、设计单位以及设计人、制图人、审批人的签名

D、会签人代表的专业、姓名
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