影响电弧偏吹的因素有().
A、气流
B、焊条偏心
C、磁场
D、焊速
参考答案:A, B, C
In relation to the Contract Law of China:
(b) State the conditions to be met for an effective acceptance. (6 marks)
切削液可分为()
A.油基切削液和水基切削液
B.复合油和极压油
C.乳化液和合成液
D.极压油和合成液