事故情况下,在全站无电后,必须将电容器支路断路器()。
A、先合上
B、先断开
C、先更换
D、先不动
参考答案:B
Lucy often goes to school on foot, doesn’t she?
A.takes walk at school
B.walks to school
C.goes to school early
D.goes to school with feet
凝胶剂的常用基质是()
A.硅酮
B.硬脂酸钠
C.聚乙二醇
D.黄凡士林
E.卡波姆