单项选择题
How many adult life jackets are required on board a ship?（）
A.Enough for 100 percent of the persons allowed on board B.One for each work station and industrial work site C.Enough for 150 percent of the persons allowed on board D.Both A and B above
单项选择题 Heavy fuel oils when spilled are（）.
单项选择题 Each life preserver must be readily accessible to the person for whom it is intended while he or she is（）.
单项选择题 Each life jacket light that has a non-replaceable power source must be replaced（）.
