自由沉降的意思是（）。A、颗粒在沉降过程中受到的流体阻力可忽_爱下问搜题

搜题请搜索小程序“爱下问搜题”

问题单项选择题

自由沉降的意思是（）。

A、颗粒在沉降过程中受到的流体阻力可忽略不计

B、颗粒开始的降落速度为零，没有附加一个初始速度

C、颗粒间不发生碰撞或接触的情况下的沉降过程

答案

参考答案：C

改错题

短文改错。
     此题要求改正所给短文中的错误。对标有题号的每一行作出判断；
     如有错误（每行只有一个错误），则按下列情况改正：
     此行多一个词：把多余的词用斜线划掉，在该行右边横线上写出该词，并也用斜线划掉。
     此行缺一个词：在缺词处加一个漏字符号（∧），在该行右边横线上写出该加的词。
     此行错一个词：在错的词下划一横线，在该行右边横线上写出改正后的词。
     注意：原行没有错的不要改。

What should you do when you parents become angry? If your
parents got mad, try to have a conversation with them
about it. Remembering not to shout at them. They usually
will try to change, but they will take some time because
they get angry all their life,and that is all they know.You
might have to change for your method a couple of times.
Do any nice things for your parents that they don't expect
-like cooking, doing the dishes, washing clothes, or clean
the floors. If this doesn't work, bring in friend that you
feel comfortable,and have him or her help you.

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填空题

机位应当设置（）色机位作业等待区、（）色机位安全线。