单项选择题
How many life buoys（）on board with self-igniting light?
A.there exist B.there is C.there are D.are there
单项选择题 Frapping lines are fitted to lifeboat davits to（）.
单项选择题 Fire fighting equipment requirements for a particular vessel may be found on the（）.
单项选择题 Each open lifeboat carried on a vessel on an international voyage must have（）.
