为了防止变压器油劣化一般往油中加()
A.防锈剂
B.抗氧化剂
C.破乳化剂
参考答案:B
单项选择。
We will go to every person in his family. [ ]
A. look
B. watch
C. visit
D. find
判定数组【5,6】表示允许有5个不合格的样品,但不允许有6个不合格样品。