A class C fire would be burning（）.

单项选择题A class B fire is most successfully fought by（）.

A.preventing oxygen from reaching the burning material
B.cooling the burning material below its ignition temperature
C.using the extinguishing agent to make the burning material fire-resistant
D.using the extinguishing agent to absorb the heat

单项选择题A Certificate of Inspection issued to a small passenger vessel describes（）.

A.the mimimum fire extinguishing equipment，lifejackets，survival and rescue craft she must carry
B.the name of the managing operator
C.any special conditions or restrictions on her operation
D.All the above

单项选择题A carburetor is required to have a safety device called a(n)（）.

A.pressure release
B.backfire flame arrestor
C.automatic shut off
D.flow valve

单项选择题A carbon dioxide fire extinguisher should be recharged（）.

A.at least annually
B.whenever it is below its required weight
C.only if the extinguisher has been used
D.before every safety inspection

单项选择题The emergency signal for fires is sounded on the ship’s whistle and general alarm as（）.

A.a continuous ringing for 10 seconds
B.one short ring followed by one long ring
C.two long rings of at least 20 seconds
D.a continuous ringing until the fire is extinguished