单项选择题
A.marline or ratline wound along the grooves of a rope
B.narrow strips of light canvas or cotton cloth spiral-wrapped along the rope
C.marline tightly wound on the rope by means of a board or mallet
D.a splice made by laying the strand of one rope into the vacated grooves of another rope
单项选择题 Separating both blocks of a tackle to prepare it for reuse is called（）.
单项选择题 opes or wires attached to derricks to prevent them from swinging during cargo handling operations are（）.
单项选择题 On your vessel，a wire rope for the cargo gear shows signs of excessive wear and must be replaced. In ordering a new wire for this 10-ton boom，what safety factor should you use?（）