答案:A
正常成人PR间期为()。
A.0.10~0.20秒
B.0.12~0.20秒
C.0.06~0.08秒
D.0.32~0.44秒
E.0.08~0.22秒
You are on watch at sea a man falls overboard on the port side, forward near No. 1 hatch. What of the following should you do first?().
A.Call the master
B.Put the helm hard over toward the port side
C.Sound the alarm to arouse all hands
D.Stop the engines