单项选择题
A.hydrocarbon gas B.carbon monoxide gas C.carbon dioxide gas D.freon gas
A.oil stained shoes or clothing B.sharp objects that may puncture or damage the liferaft C.matches or cigarette lighters D.drugs or paraphernalia not approved by a medical doctor
A.cutting the old line off and renewing same B.an approved servicing facility ashore C.opening the case and replacing the entire line D.one of the ship's officers