单项选择题
A.cheek B.gypsy C.sheave D.drum
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
A.has a spray pattern 12 feet in diameter B.can be used in conjunction with both 1-1/2 inch and 2-1/2 inch all-purpose nozzles C.has a 90°bend at its discharge end D.has a screw thread end which connects to the all-purpose nozzle