单项选择题
A.12mmB.16mmC.20mmD.25mm
A.管子卡盘B.板牙刀C.进刀手轮D.割刀架
A.1/2~2inB.1/2~3inC.1/2~4inD.1/2~6in
A.D=DPB.D=D+PC.D钻=D-PD.D=D-P÷D
微信扫一扫,加关注免费搜题