절삭속도(cutting speed)의 단위를 바르게 나타낸 것은

절삭속도(cutting speed)의 단위를 바르게 나타낸 것은?
① m/min ② mm/min
③ mm/rev ④ rpm

Results (English) 1:

Cutting speed (cutting speed) shows the right unit of?① m/min ② mm/min③ mm/rev ④ rpm

Results (English) 2:

It is shown correctly a unit of the cutting speed (cutting speed)?
① m / min ② mm / min
③ mm / rev ④ rpm

Results (English) 3:

cutting speed (speed cutting) unit to correct the out of.① m / min ② mm / min③ mm / rev ④ rpm