单项选择题
A.5.5mm/sB.7.0mm/sC.8.0mm/sD.9.5mm/s
A.6mm/sB.8mm/sC.12mm/sD.14mm/s
A.0.45-0.60B.0.60-0.75C.0.75-0.90D.0.90-1.0