单项选择题
A.0.1mm~0.2mm B.0.2mm~0.4mm C.0.3mm~0.5mm D.0.4mm~0.6mm
A.1/3 B.1/4 C.1/5 D.1/2
A.11.5~15 B.12~16 C.12.5~15 D.13.5~16