单项选择题
The term "discharge", as it applies to the pollution regulations, means（）.
A.spilling B.leaking C.dumping D.All of the above
单项选择题 To prevent the spread of fire by convection you should （）.
单项选择题 When welding or burning aboard a vessel, you must be certain that the space （）.
单项选择题 The most likely place for a fire to start through the process of spontaneous combustion is in （）.
