在线搜题找答案-搜题搜试题搜试卷搜题库搜答案就上赞题库……

问答题Complete each group of sentences with the two adverbs given. hard; hardly a. He works ______ . b. He ______ ever reads books now.

问答题一个绕有500匝导线的平均周长50 cm的细环，载有 0.3 A电流时，铁芯的相对磁导率为600． (1) 铁芯中的磁感强度B为__________________________ T ． (2) 铁芯中的磁场强度H为____________________________ A m． (m0 =4p×10-7 T·m·A-1)