单项选择题
A.5mm±1mmB.5mm±2mmC.6mm±1mmD.6mm±2mm
A.90°-120°B.120°-180°C.180°-270°D.270°-360°
A.2s-3s,3°-6°B.2s-3s,4°-7°C.3s-5s,3°-6°D.3s-5s,4°-7°