可以用来输送清水,扬程不高,但流量可以随负荷变化而变化,其结构形式为分段式,这种泵为()。
A.离心式冷凝水泵
B.离心式浅水泵
C.离心式锅炉给水泵
D.离心式潜水泵
参考答案:C
At the beginning of a speech, it is very important to grab the audience's attention and make them interested in ____ you have to say.
A.what
B.which
C.that
D.who
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