将铜片和铝片用导线连接后插入盛有浓硝酸的烧杯中组成原电池,此原电池的负极及其电极反应分别是 A. Al, Al- 3e-=Al3+ B. Cu, Cu-2e-=Cu2+ C. Al, 2H++2e-=H2↑ D. Cu, 2H++NO3-+e-=NO2↑+H2O 答案:B18.I think the director's attitude ________ this program will decide what we should do next.( )A.towardsB.atC.onD.for.