题目: 实验室里不同化学试剂的保存方法不尽相同,①NaOH溶液 ②大理石 ③NaCl溶液 ④稀硝酸4种试剂通常各自存放在下列图示的某种试剂瓶中。按照试剂瓶的顺序存放试剂序号正确的是( )A.①②③④B.②①④③C.②③④①D.②①③④ 答案: 答案:D
题型:选择题 _______for the work, he went to sleep at ease.A.Well prepared B.Preparing C.Being preparedD.Getting ready 查看答案