题目

I (频繁地) ask people what is the meaning of life? 答案：【1】frequently/constantlyA、B、C都是金属，A中混有C时，A先腐蚀；A与B组成原电池时，A为电池的正极。A、B、C三种金属的活动性顺序为：A．A>B>C       B．A>C>B       C．B>A>C        D．B>C>A