采用闸阀调节法时,当闸阀关小,管路阻力增大,则管路中的流量(),扬程()。
A.增加;不变
B.增加;减小
C.减小;增加
D.不变;减小
参考答案:C
As a result of the radio _______ for help for the earthquake victims, over a million pounds have been
raised. [ ]
A. invitation
B. advertisement
C. appeal
D. program
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