单项选择题
A.SOS B.Mayday C.Securite D.PAN
Which one of the following is the safety signal?（）.A.SS...
单项选择题Which one of the following is the safety signal?（）.
A.SSS B.TTT C.XXX D.FFF
Your vessel has been damaged and is taking on water，but...
单项选择题Your vessel has been damaged and is taking on water，but you do not require immediate assistance. You would preface a message advising other vessels of your situation with（）.
A.Mayday-Mayday-Mayday B.Pan-Pan (3 times) C.Securite-Securite-Securite D.SOS-SOS-SOS
The urgency signal concerning the illness of persons on...
单项选择题The urgency signal concerning the illness of persons on board ship is（）.
A.MAYDAY B.PAN C.SECURITE D.ATTENTION
