旋磁器件
参考答案:
利用旋磁材料或旋磁介质做成的器件。
I supported him in time , otherwise he off the bike .
A.might fall
B.would fall
C.should have fallen
D.would have fallen
新组装或重新组装的轮对同一车轮相互垂直的直径差不得大于()mm。
A.0.5
B.1
C.1.5
D.2