On a ship，a fixed carbon dioxide or other approved system must be installed（）.

单项选择题On a ship，a fire drill shall be conducted once every（）.

A.week
B.month
C.crew change
D.other week

单项选择题On a ship，a cabinet or space containing the controls or valves for the fixed firefighting system must be（）.

A.posted with instructions on the operation of the system
B.ventilated and equipped with explosion-proof switches
C.painted with red and black diagonal stripes
D.equipped with a battery powered source of emergency lighting

单项选择题On a class B fire，which portable fire extinguisher would be the LEAST desirable?（）

A.Carbon dioxide
B.Water (stored pressure)
C.Dry chemical
D.Foam

单项选择题Oily rags stored in a pile that is open to the atmosphere are a hazard because they may（）.

A.deteriorate and give off noxious gasses
B.spontaneously heat and catch fire
C.attract lice and other vermin and serve as a breeding ground
D.None of the above

单项选择题Normally，potable water systems are connected directly to the（）.

A.fire-main system
B.feed-water system
C.freshwater sanitary system
D.domestic water tank