单项选择题
A.0.10%~0.25% B.0.25%~0.6% C.0.6%~1.3% D.1.3%~2%
A.160° B.165° C.170° D.175°
A.磁力线 B.电流 C.磁性 D.感应电流
A.模数、周节 B.模数、齿宽 C.周节、齿宽 D.模数、压力角
微信扫一扫,加关注免费搜题