题目:
Air line lubricators are used in compressed air systems to lubricate ().
A.the suction and discharge valves
B.tools and equipment served by compressed air
C.air line reducing valves
D.all of the above
答案:
参考答案:B
Air line lubricators are used in compressed air systems to lubricate ().
A.the suction and discharge valves
B.tools and equipment served by compressed air
C.air line reducing valves
D.all of the above
参考答案:B