问题
单项选择题
流体在流动过程中，产量（或渗流速度）、压力随时间而变化的流动称为（）。
A.稳定流动
B.不稳定流动
C.弹性稳定流动
D.弹性不稳定流动
答案
参考答案：B
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流体在流动过程中，产量（或渗流速度）、压力随时间而变化的流动称为（）。
A.稳定流动
B.不稳定流动
C.弹性稳定流动
D.弹性不稳定流动
参考答案：B
| 完形填空。 | |||
| I'm Mary. I'm from England. __1__ now, I'm in Shanghai. I have a new friend. __2__ is a Chinese girl and her __3__ is Liu Ying. We are both in Class 2, Grade 7. We are __4__ . Liu Ying has two __5__ eyes, but her mouth is small. Her ears are big. Her legs are long and her arms are __6__ , too. Her favorite color is __7__ . Today she is in a white __8__ . It's very nice. White is my favorite __9__ , too. We are the __10__ age. She is twelve, too. | |||
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