用输入—输出法测定锅炉热效率时,测量给水流量的一次测量元件处的差压,应至少用()套差压测量装置,以达到测量结果的相互一致。
A.1
B.2
C.3
D.4
参考答案:B
背景资料
写出应急反应的实施原则。
—Have you got some water to drink?
—Here you are. There _______ still some in the bottle. [ ]
A. are
B. has
C. is
D. have