单项选择题
A.0.8 m B.0.9 m C.1 m D.1.2 m
A.1/200 B.1/450 C.1/750 D.1/800
A.2‰ B.3‰ C.4‰ D.5‰
A.0.03 mm B.0.05 mm C.0.06 mm D.0.07 mm
微信扫一扫,加关注免费搜题