Which of the listed fire extinguishers cannot be easily recharged aboard ship?（）

A.on the windward side of the opening
B.on the leeward side of the opening
C.at a right angle to the wind direction
D.so that the obstruction of your body will protect you from the fumes

A.center of gravity is lowered
B.center of buoyancy is lowered
C.reserve buoyancy is unchanged
D.hull freeboard is increased

A.The agent is considered nontoxic at room temperature in low concentrations
B.The agent is less effective than carbon dioxide
C.Halon primarily extinguishes the fire by cooling
D.The agent cannot be used on electrical fires because it leaves a residue