单项选择题
All of the following are part of the fire triangle except（）.
A.electricity B.fule C.oxygen D.heat
单项选择题 All of the following records are usually maintained by the watch-standing officers aboard a vessel except the（）.
单项选择题 All portable fine extinguishers must be capable of being（）.
单项选择题 All the cargo holds must be（）cleaned out（）meet the requirement of the cargo surveyor.
