单项选择题
What is placed on the underside of an inflatable liferaft to help prevent it from being skidded by the wind or overturned? （）
A.Ballast bags B.A keel C.Strikes D.Sea anchor
单项选择题 What is meant by the term “broaching to”? （）
单项选择题 What generally occurs when the land is cooler than the nearby water? （）
单项选择题 Under the IALA-A Buoyage System，a green spar buoy with a triangular topmark would indicate that the buoy（）.
