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
A heavy，thick-walled tube，usually steel，used between the drill pipe and the bit in the drill stem to weight the bit in order to improve its performance is called a（）.
A large vessel is equipped with a controllable pitch propeller. Which statement is TRUE?（）
Permanent magnetism is found in（）.
A flooded leg on a liftboat would adversely affect the vessel’s stability underway by（）.
A fishing vessel displaying the lights shown is（）.
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 helmsman receives the command “Right 15 degrees rudder.”The helmsman’s IMMEDIATE reply should be（）.
A hand held instrument used to measure distances between objects and the ship is a（）.
A heavy steel curved arch constructed athwartships and above the after deck on a towing vessel is sometimes called a（）.
Between 1830 hrs and 1850 hrs this day，strong gusty winds（）by my vessel，in consequence of which the vessel’s four mooring lines were broken.