题目

You must a_______ to your sister for being so rude.   答案：apologize现有0.01mol／L的下列溶液：①CH3COOH ②NaHCO3  ③NaHSO4  ④KOH ⑤H2SO4 按pH由小到大的顺序排列的是 (   ) A．⑤③①②④       B．③⑤①②④     C．⑤②③①④       D．④②①③⑤