当滚动轴承采用油润滑时，其轴端的密封应采用（）最合适。
A.毡圈密封
B.隙缝密封
C.唇型密封圈
参考答案：C
Brian has to get up early to catch the first bus tomorrow.
Please .
A．wake up his
B．wake his up
C．wake up him
D．wake him up
遇到大雨、大雾、雷击和（）级以上大风等恶劣天气，应当停止进行露天、高处、起重吊装和打桩等作业。
A.4.0
B.5.0
C.6.0
D.7.0
