粉尘采样有哪些方法?
参考答案:
粉尘采样的方法有:
(1)预测流速法等速采样;
(2)皮托管平行采样法等速采样;
(3)静压平衡法等速采样;
(4)动压平衡法等速采样等。
--Which play shall we go and see?
----____________________.
A.I'm afraid we can't
B.I don't think it's interesting
C.Yes, I quite agree with you
D.I'll leave it to you
截止到2004年,我国运动员在世界无线电测向比赛中共夺得过()枚金牌。
A.10
B.11
C.12