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【单选题】
管路在流量为qV1时需要的外加压头为H1。现有一台离心泵，在流量为qV1时的压头为H2。若H2大于H1，则在将该泵安装于该管路时，泵的流量qV和压头H满足（）A.
qV=qV1 ， H>H2
B.
qV>qV1 ， H1
C.
qV ， H
D.
qV>qV1 ， H>H2
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举一反三
【多选题】一般来说，PID控制器参数微分系数Td与控制效果有密切关系，如下哪些说法是准确的。
A.
Td 也大，则有利于提高响应速度
B.
Td 的数值太大和太小都会引起超调
C.
Td 的可以取零值
D.
Td 取值与控制精度要求无关
【单选题】听力原文：W: This is too much. I have been waiting for my meal for more than half an hour. M: I know, but you see the restaurant is full and we're shorthanded today. Q: How does the woman feel? (15)
A.
She is satisfied.
B.
She is tired.
C.
She is impatient.
D.
She is happy
【单选题】Miss Sullivan tried to make Helen understand that "mug" is mug and "water" is water, but Helen kept confusing them, then Sullivan _________.
A.
dropped the subject once and for all
B.
continued to do it until she realized that her repeated attempts made Helen tired and angry
C.
became impatient and unhappy and gave it up
D.
dropped it for a while and picked it up when there was an opportunity
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