球墨铸铁是如何获得的?
参考答案:
通过在浇注之前,往铁液中加入少量球化剂(通常为镁、稀土镁合金或含铈的稀土合金)和孕育剂(通常为硅铁),使铁水凝固后形成球状石墨而获得的。
—Pick, I did very well in the maths exam last week.
—Congratulations, Jim! And I did _____. I got a full mark and 20 extra points.
A.no better
B.not better
C.no worse
D.even worse
判断原厂保修是否过期,以什么条件为准?()
A、仅以时间是否到期为准
B、仅以里程是否到达为准
C、以时间及里程的后到为准
D、以时间或里程的先到为准
E、以车辆损坏程度为准