单项选择题
To remedy a leaking fire hose connection at the hydrant，secure the valve and（）.
A.replace the gasket in the male coupling B.reduce fire pump pressure C.replace the gasket in the female coupling D.rethread the male coupling
单项选择题 To prevent the spread of fire by conduction you should（）.
单项选择题 To lubricate the swivel or remove corrosion from a fire hose coupling，you should use（）.
单项选择题 To determine if a CO2 fire extinguisher is fully charged，you would（）.
