变压器过负荷保护安装在电源侧,一般采用()接线.
A、一相式
B、两相式
C、三相式
D、交叉式
参考答案:A
Every possible means ________, but the teacher as well as the students ________ found a solution to the problem yet.
A.has been tried; hasn’t
B.has tried; haven’t
C.have tried; haven’t
D.have been tried; hasn’t
家庭内部非得地共有人也可直接代户主签字。