单项选择题
A rolling hitch can be used to（）.
A.make a temporary eye B.mouse a hook C.secure a line around a spar D.shorten a line
单项选择题 A J-chaser is used to（）.
单项选择题 A fid is a（）.
单项选择题 A common class of wire rope is the 6X37 class. What does the 37 represent?（）
