单项选择题
According to the regulations for lifeboat falls，which action must be taken with the falls no later than 5-year intervals?（）
A.Proof tested B.End-for-ended C.Renewed D.Weight tested
单项选择题 According to the regulations for life boat falls，which action must be taken at 30-month intervals?（）
单项选择题 A sheave is a（）.
单项选择题 A sea anchor is（）.
