单项选择题
The cheek length of a block in inches should be about（）.
A.three times the circumference of a manila line B.five times the diameter of a manila line C.twice the diameter of its sheaves for manila line D.twenty times the diameter of a manila line
单项选择题 The 12-foot low-velocity fog applicator（）.
单项选择题 Splices made in nylon should（）.
单项选择题 Right-laid line should be coiled（）.
