单项选择题
A.0.20~0.30mm B.0.22~0.34mm C.0.24~0.37mm D.0.30~0.55mm
A.0.20~0.31mm B.0.22~0.34mm C.0.24~0.37mm D.0.30~0.55mm
A.90% B.85% C.80% D.75%