An upright vessel has negative GM. GM becomes positive at the angle of loll because the（）.

单项选择题An inland oil barge must have equipment available to remove an on-deck oil spill of at least（）.

A.one barrel
B.two barrels
C.five barrels
D.ten barrels

单项选择题A shroud is（）.

A.any wire running fore-and-aft on a ship
B.any wire with a fiber core
C.a heavy wire extending from the trunk of the mast to the head of the boom
D.a heavy wire extending from the mast，atwartships to the deck，to support the mast

单项选择题A pumproom is suspected of accumulating gases after a ventilation machinery breakdown. Where should the combustible gas indicator case be placed when testing the pumproom atmosphere for combustible gases?（）.

A.In the lower level of the pumproom
B.In the middle level of the pumproom
C.In the upper level of the pumproom
D.On the deck outside the pumproom

单项选择题A partial deck in a hold is called a(n)（）.

A.weather deck
B.orlop deck
C.shelter deck
D.main deck

单项选择题A device used to tighten up remaining slack in wire rope when you are making up to a tow in inland waters is a（）.

A.tripping line
B.tripping bracket
C.norman pin
D.steamboat ratchet