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问题 单项选择题

称二级支气管的是（）。

A.气管

B.左、右主支气管

C.肺叶支气管

D.肺段支气管

E.环状软骨

答案

参考答案：C

选择题

下端固定在水平地面上的劲度系数为的轻弹簧，竖直放置长度为原长，有一质量为的小球，轻轻地从轻弹簧上端静止释放，小球随后只在竖直方向运动，不计系统机械能的损失，弹簧一直在弹性限度内，以下说法正确的是(   )

A．小球下落时其速度刚好为0

B．小球在最低点加速度刚好等于，但方向竖直向上

C．当弹簧的长度为时弹簧弹性势能最大

D．小球下落到最低点的经历时间比从最低点回到最高点要的时间长一些
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完形填空
阅读下面对话，从方框内 7 个选项中选择 5 个恰当的句子完成此对话，并将其番号填入题前括号 内。
A. How old is it?
B. Where did you go?
C. Sounds interesting.
D. When did you go there?
E. There are many things to play with.
F. How do you like it?
G. How did you get there?
A. Jack, I hear that you’ve just come back from Hong Kong?小题1:
B. Oh, it’s wonderful. It’s one of the most interesting places I have ever seen.
A.小题2:
B. I went to many places, but I’m interested in Disneyland most.
A. Could you tell me something about it?
B. Well, it has lots of cartoon characters there, like Mickey Mouse, Donald Duck and so on.
A. 小题3:Tell me more about it.
B. 小题4:Such as the roller coaster.
A.小题5:
B. I went there by plane.
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