What is NOT a distress signal?（）

单项选择题What is NOT a distress signal?（）

A.A continuous sounding of the fog horn
B.Firing a gun every minute
C.Five or more short rapid blasts on the whistle
D.A square flag and ball flown from the mast

单项选择题The service life of distress signals must be not more than（）.

A.forty two months from the date of manufacture
B.thirty six months from the date of the last inspection
C.twenty four months from the date of approval
D.twelve months from the date of purchase

单项选择题The radiotelegraph alarm signal may be used to announce（）.

A.that a distress message will follow
B.a request for assistance in searching for a man overboard
C.an urgent warning about a cyclone
D.All of the above

单项选择题The distress message of a ship should include considerable information which might facilitate the rescue. This information should（）.

A.ALWAYS be included in the initial distress message
B.be sent to a MSA station FIRST
C.be transmitted as a series of short messages，if time allows
D.include the vessel's draft

单项选择题The color of rockets，shells，or rocket parachute flares used to indicate that the vessel is in distress and requires immediate assistance is（）.

A.white
B.green
C.red
D.yellow