问题
单项选择题
增大接地网的()是减小接地电阻的主要因素。
A、深度
B、导体截面积
C、面积
D、体积
答案
参考答案:C
增大接地网的()是减小接地电阻的主要因素。
A、深度
B、导体截面积
C、面积
D、体积
参考答案:C
We feel 小题4:__ sorry for the loss of lives. There is小题5:__ we can do to bring the students back, but we can try to prevent (防止) such things from 小题6:__ again. You should do the following things to prevent a stampede (踩踏)。 After class or school, don’t rush out at the same time. Wait until there are小题7:__ people trying to leave.When you walk with a crowd of people, stay alert (警惕的) and 小题8:your steps. Don’t play around. Be familiar with your 小题9:_ and learn where the safety exits are. When there’s pushing and squeezing (挤),don’t move and try to hold on to something. 小题10:___ stay in a corner until the crowd leaves. |