原料的K值低说明含()多。 A.芳烃 B.烯烃 C.烷烃 D.环烷烃 发布时间:2017-09-16 22:48 │ 来源:www.tikuol.com 题型:单项选择题 问题: 原料的K值低说明含()多。A.芳烃B.烯烃C.烷烃D.环烷烃
题型:单项选择题 —How many lessons do you usually have a day? —Six lessons a day, and each of them _____ 45 minutes. [ ]A. last B. lasts C. have 查看答案