颈椎牵引中的重量应为（）
A.1／3体重
B.1／2体重
C.1／10体重或稍超过
D.1／15体重或稍超过
E.1／20体重或稍超过
参考答案：C
每年的3月______日是妇女节，______月______日是国际劳动节．
It is required that ships proceeding at sea should keep continuous watch on（）.
A.VHF channel16 and 13
B.appropriate DSC distress and safety frequency
C.INMARSAT TDM message channel
D.VHF channel 70 and channel 8
