单项选择题
A.year B.two years C.four years D.five years
By regulation，cargo tanks must be inert before and duri...
单项选择题By regulation，cargo tanks must be inert before and during what operation?（）.
A.Stripping B.Loading C.Cleaning D.Crude oil washing
By regulation，cargo tank atmosphere must be inert befor...
单项选择题By regulation，cargo tank atmosphere must be inert before and during which operation?（）
A.Stripping B.Loading C.Cleaning D.All of the above
An oil tanker，except as provided for otherwise，might di...
单项选择题An oil tanker，except as provided for otherwise，might discharge certain amount at certain rate of oil or oily mixtures into sea when（）.
A.she is not within a special area B.she is within a special area C.she has just departured from a special area D.she is about to enter a special area
