精重苯聚合时,要控制在古-茚含量为:()。
A.5-8%
B.10-20%
C.20-25%
参考答案:C
检查减速器轴承是否发热,可用()。
A、鼻闻
B、目视
C、手摸
D、监听
Henry broke the window .I’ll ask him why __________ .
A.did he do that
B.he did that
C.had he done that
D.he had done that