单项选择题
A cargo tank that is initially gas freed，can be inerted by introducing inert gas by a process known as（）.
A.dilution B.displacement C.precipitation D.Either A or B
单项选择题 A “wet cargo” refers to（）.
单项选择题 A “strongback” refers to a（）.
单项选择题 A “dangerous cargo manifest” is needed for you to carry a combustible cargo. You should obtain the shipping papers to make this “manifest” from the（）.
