When fighting a fire in an enclosed space，the hose team should crouch as low as possible to（）.

单项选择题When electrical equipment is involved in a fire，the stream of dry chemicals should be（）.

A.aimed at the source of the flames
B.fogged above the equipment
C.shot off a flat surface onto the flames
D.used to shield against electrical shock

单项选择题When dry chemical extinguishers are used to put out class B fires，there is a danger of reflash because dry chemical（）.

A.is not an effective agent on Class B fires
B.does little or no cooling
C.dissipates quickly
D.is rapidly absorbed by the liquid

单项选择题A shipboard Oil Pollution Emergency Plan is required of（）.

A.all vessels，regardless of size and commercial application
B.any barge or ship constructed or operated in such a manner that no oil in any form can be carried aboard
C.an oil tanker of 150 gross tons and above，or other ship of 400 gross tons and above
D.an oil tanker of 400 gross tons and above，or other ships of 150 gross tons and above

单项选择题Flooding of any compartment in a ship that results in a serious loss of reserve buoyancy will always（）.

A.increase the trim
B.increase ship stability
C.cause a serious list
D.decrease the heeling moment

单项选择题A group of crew members standing by in case of an emergency in order to assist other teams in action if necessary is a（）.

A.Fire team
B.Rescue team
C.Emergency team
D.Control team