单项选择题
What material may be substituted for zinc when making a poured metal socket ending to a wire rope（）.
A.Lead B.Babbitt C.Solder D.Nothing
单项选择题 What is the main purpose of dunnage（）.
单项选择题 What is the bow type anchor shackle primarily used for（）.
单项选择题 What is NOT running rigging（）.
