井下輸送機(jī)操作工單項(xiàng)選擇題每日一練(2019.05.05)

A.1/2
B.1/3
C.1/4
D.1/5

A.40°
B.45°
C.50°
D.55°

A.1
B.2
C.3
D.4

A.20%～30%
B.30%～40%
C.60%～70%
D.50%～60%

A.10%～20%
B.20%～30%
C.40%～50%
D.50%～60%