单项选择题
If you log a distress message，it must include the（）.
A.sea state B.names of witnesses C.time of its occurrence D.wind direction and velocity
单项选择题 If you are transmitting a distress message by radiotelephone you should（）.
单项选择题 How is “radio silence” imposed?（）
单项选择题 Distress signals may be（）.
