保险合同的( )意味着订立的保险合同对双方当事人产生法律约束力。
A.生效
B.履行
C.解除
D.有效订立
参考答案:D
()is a category assigned to products or services having the same fimctional use but different technical characteristics. It is not same as quality.
A.Problem
B.Grade
C.Risk
D.Defect
在直流发电机与电瓶并联供电系统中,返流故障的危害是:().
A.发电机过载
B.发电机欠载
C.蓄电池过量充电
D.蓄电池过量放电