题目

下列“实验结论”与“实验操作及现象”相符的一组是( )选项实验操作及现象实验结论A向某溶液中加入AgNO3溶液,有白色沉淀生成该溶液中一定含有Cl-B向某溶液中加入稀盐酸,有无色气体产生该溶液中一定含有CO32-C向某溶液中加入BaCl2溶液,有白色沉淀生成该溶液中一定含有SO42-D向某溶液中加入NaOH溶液,立即产生红褐色沉淀该溶液中一定含有Fe3+ A.A B.B C.C D.DJoe wasn't at home yesterday. He _____ to help with Eve's English. [     ]A. was asking     B. is asked         C. is asking       D. was asked
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