什么叫做供水管道的流速?
参考答案:
供水管道中的流速是指水流在管道中的流动速度,一般以m(米)/s(秒)来表示。
具有化瘀止血,活血定痛功效的药物是()
A.茜草
B.白及
C.白茅根
D.三七
E.地榆
I never saw him, I can remember, reading anything but newspapers.[ ]
A. as far as
B. as soon as
C. unless
D. until