A.a 2-second blast every 20 seconds
B.a 4-second blast every 20 seconds
C.an 8-second blast every 30 seconds
D.a 10-second blast every 30 seconds
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A.turn off all lights that interfere with the navigation lights
B.turn on all available working lights on deck
C.ring the bell rapidly for five seconds once a minute
D.display two black diamonds in a vertical line during the day
A.Aye Aye Sir
B.Right 15 degrees rudder
C.Rudder is right 15 degrees
D.No reply is necessary，just carry out the order
A.heavy-walled drill pipe
B.tool joint
C.down hole tool
D.drill collar
A.main brace
B.tow span
C.jockey bar
D.None of the above
A.one sidelight
B.one sidelight and a masthead light
C.one sidelight and two masthead lights
D.both sidelights of a vessel and her masthead light(s)
最新試題
After sending a message describing the symptoms of an ill crew member，you receive a message containing the code MRL. This means（）.
A fire pump may be used for other purposes if（）.
A fishing vessel displaying the lights shown is（）.
A large basin cut into the shore，closed off by a caisson，and used for dry docking of ships is known as a（）.
A large valve，usually installed above the ram preventers，that forms a seal in the annular space between the pipe and wellbore or，if no pipe is present，on the wellbore itself is called the（）.
A fire has broken out on the stern of your vessel. You should maneuver your vessel so the wind （）.
Permanent magnetism is found in（）.
Permanent magnetism is caused by（）.
A jack-up drilling unit elevated on the Outer Continental Shelf must have a fog horn that will sound（）.
It is not necessary to declare（）in the Health List.