单项选择题
A.combustible liquid B.flammable gas C.flammable liquid D.flammable solid
Before starting a gasoline engine on a motorboat，you sh...
单项选择题Before starting a gasoline engine on a motorboat，you should make sure for safety that（）.
A.the gasoline tank is full B.the bilges，cabins，etc. are thoroughly ventilated C.you have fresh water on board D.Each of the above is followed
Before entering a tank，always check the vapor content（）...
单项选择题Before entering a tank，always check the vapor content（）a combustible gas indicator.
A.with B.by C.of D.for
After the initial cleaning of flue gas in an inert gas ...
单项选择题After the initial cleaning of flue gas in an inert gas system the gas is passed through what device for final cleaning?（）.
A.Scrubber B.Demister C.Deck water seal D.Final filter
