单项选择题
A.0.1L/(s·m)B.0.2L/(s·m)C.0.3L/(s·m)D.0.5L/(s·m)
A.0.15mmB.0.1mmC.0.25mmD.0.2mm
A.间隙B.线圈吸引力C.补偿行程D.弹簧弹力