单项选择题
Heavy fuel oils when spilled are（）.
A.more harmful to sea life than lighter oils B.easier to clean up than lighter refined oils C.less harmful to sea life than lighter oils D.not a real threat to marine life
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（）.
单项选择题 A person reports to you with a fishhook in his thumb. To remove it you should（）.
