题目

--What did the teacher ________ just now?         --He _____ us that Changjiang is the longest river in China. A. tell, says           B. ask, said           C. say, told 答案：C下列各组物质在pH=1的溶液中能大量共存且得到无色溶液的是（ ）A．BaCl2  NaOH  NaCl  CaCl2B．Mg（NO3）2   KNO3    NaCl    ZnSO4C．CuSO4  KCl  Na2SO4  NaNO3D．BaCl2  CaCl2   Al（NO3）3    KCl