煤矿井下造成短路的主要原因有() A.绝缘击穿 B.绝缘电阻降低 C.机械损伤 D. 发布时间:2021-02-17 02:26 │ 来源:www.tikuol.com 题型:多项选择题 问题: 煤矿井下造成短路的主要原因有()A.绝缘击穿B.绝缘电阻降低C.机械损伤D.电压过高E.误操作
题型:多项选择题 I can think of many cases _____ students obviously knew a lot of English words and expressions but couldn't write a good essay.A. why B. which C. as D. where 查看答案