Grinding to eliminate shallow surface defects should be done（）.

单项选择题Fuel oil tank vents are fitted with a screen which will stop（）.

A.oil from flowing out of the tank vent
B.air from entering the tank vent
C.vapors from leaving the tank vent
D.flames on deck from entering the tank vent

单项选择题Freeboard is measured from the upper edge of the（）.

A.bulkwark
B.deck line
C.gunwale bar
D.sheer strake

单项选择题Forecastle deck is located in the ship’s（）.

A.bow stem
B.stern
C.portside
D.starboard side

单项选择题Electric cargo winches have an overload safety device which normally cuts the current to the winch motor（）.

A.after torque causes line pull to exceed the rated capacity of the winch
B.before the line pull reaches the rated capacity of the winch
C.when the line pull reaches the breaking strength of the fall
D.before the safe working load of the fall is reached

单项选择题Damaged bulkheads often take a permanent set which is independent of the panting or bulge caused by water pressure. To control this，you should（）.

A.install shoring so the shoring supports the damaged bulkheads without pushing on them
B.install shoring so that it pushes on the damaged bulkhead while supporting it
C.use jacks or chain falls to remove the set before installing shores
D.place sandbags by the bulkhead without installing shores