单项选择题
What equipment is customarily used when seamen are working on a stage rigged over the side of a vessel（）.
A.Jacob's ladder B.Manropes C.Heaving lines D.All of the above
单项选择题 What does the term end-for-end refer to in regard to a wire towing hawser（）.
单项选择题 What best describes an anchor buoy（）.
单项选择题 What are the two main types of stud link chain（）.
