. Our TV sets sell well, but ten years ago no one could have imagined such a big share in the market that they ____.

A．were having

B．had had

C．were to have

D．had

（8分）用Pt电极电解1000mL含KNO3和Cu(NO3)2混合溶液一段时间，在两极均生成标准状况下的气体11.2L。求原混合溶液中Cu²⁺的物质的量浓度和电解后溶液中的H^＋的物质的量浓度（设电解后溶液体积不变）。