下列物质能与二氧化硅起化学反应的是[ ] ①浓硝酸 ②水 ③王水 ④氢氟酸 ⑤K 发布时间:2017-06-27 21:23 │ 来源:www.tikuol.com 题型:选择题 问题: 下列物质能与二氧化硅起化学反应的是[ ]①浓硝酸 ②水 ③王水 ④氢氟酸 ⑤KOH溶液 A.①②B.②④ C.④⑤ D.③⑤
题型:选择题 根据所给资料,回答下面问题。2006年上海市生物医药制造业主营业务收入和利润总额构成以下那个选项的主营业务收入利润率最高(主营业务收入利润率:利润额/主营业务收入)()。A.卫生材料及医药用品B.医疗器械C.中药饮片及中成药D.化学药品制剂 查看答案
题型:选择题 If the policemen had arrived two minutes later than that, the man must have been killed by the gang.A. Had the policemen arrived B. If the policemen arrivedC. If the policemen arrived D. Had the policemen had arrived 查看答案