题目: They _____ another song from Susan because she sang so well. [ ]A. requested B. needed C. ordered D. asked 答案: 答案:A
题型:选择题 三氯生是一种抗菌剂,其结构如图所示,它遇含氯自来水能生成有毒的三氯甲烷。下列说法不正确的是A.三氯生的分子式是C12H6Cl3O2B.三氯甲烷与甲烷均无同分异构体C.1 摩三氯生最多能与6 mol H2反应D.1摩三氯生最多能与7 mol NaOH反应 查看答案