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问题 列举题

列举秦汉时期我国领先于世界的科技成就。（至少3项）

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答案

造纸术；九章算术》中提出的附属概念和正负数的加减运算；麻沸散等。

阅读理解

Last year, some groups of students in their community (社区) made a survey about “How do people spend their free time? ” The following diagrams(图表) show some results of it:

Diagram (1): Hours for people of different ages who surf the Internet in a week.

Diagram (2): Different days people go to the library. (library attendance出席)

Diagram (3): Different programs people like.

小题1:People aged     spend the most time surfing the Internet every week.

A．7—16

B．17—30

C．31—55

D．over 56小题2:How many people go to the library on Saturdays?

A．About 20%.

B．About 40%.

C．Over 60%.

D．More than 80%.小题3:The three diagrams show us the results of a survey about    .

A．what people do every day

B．people’s different habits

C．people’s different lifestyles

D．how people spend their free time
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填空题

（6分）（2012•昭通）根据如图所示的实验A、B、C，回答问题（1）～（3）．

（1）实验A中，铜片上的红磷没有燃烧，说明燃烧需要　_________　．

（2）实验B中，能充分证明质量守恒定律的现象是　_________　，从微观角度分析质量守恒的原因是　_________　．

（3）实验C中的一处明显错误是　_________　，如果量取水时，仰视读数，配得的氢氧化钠溶液中溶质的质量分数将　_________　（填“偏大”、“偏小”或“不变”），配置好的氢氧化钠溶液必须密封保存，原因是　_________　．
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