单项选择题
A passenger vessel is required to have a supervised patrol when（）.
A.there are passengers berthed on board B.navigating in excess of eight hours C.the vessel has substantial wood in its construction D.there is no automatic fire-detection system installed
单项选择题 A marine chemist issues gas free certificates and is certified by the（）.
单项选择题 A large oil fire on the deck of a ship can be fought most effectively with（）.
单项选择题 A GROUP OF CREW MEMBERS TRAINED FOR FIGHTING FLOODING IN THE VESSEL are known as（）.
