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问题 填空题

1标准大气压下水的沸点为100℃,在高山上水的沸点　　       100℃。

答案

低于

题目分析：液体的沸点与大气压的关系：液体的沸点随着表面气压的增大而升高，随气压减小而降低．当在高山上时，气压减小，水的沸点会低于100℃．

点评：此题考查液体沸点与大气压的关系．液体的沸点随着表面气压的增大而升高，随气压减小而降低．

单项选择题

One day while a girl was walking in the woods she found two starving songbirds. She took them home and put them in a small (31) . She cared for them and felt great love for them.

Once the (32) and per of the two birds flew from the cage. Therefore, (33) he flew close, she grasped him (34) . She felt glad, but suddenly she felt the bird go limp. She opened her hand and (35) in horror at the dead bird.

She noticed the other bird moving back and forth on the edge of the cage. She could feel his great need for (36) . She lifted him from the cage and (37) him softly into the air. The bird circled once, twice, three times.

The girl watched delightedly at the bird’ s enjoyment. Her heart was no longer (38) with her loss. Suddenly the bird flew closer and (39) softly on her shoulder. It sang the sweetest melody that she had ever heard.

The fastest way to (40) love is to hold on it too tightly, while the best way to keep love is to give it WINGS!

（39）（）

A.stared

B.glared

C.glanced

D.shouted
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单项选择题

区分量变和质变的根本标志是( )。

A．事物的变化是否超越度的范围
B．事物变化是否显著
C．事物变化是否迅速
D．事物变化中是否有新质要素产生
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