Question

A more reactive metal can displace less reactive metal from its salt solution using this concept describe an activity to show among zn,fe,cu, zinc is most reactive and copper is least reactive

Answer 1

This situation will only exist when a metal will be more reactive than the metal whose salt solution is placed ( displacement reaction )
if we look at the reactivity series then we can clearly see that Zn is most reactive
Iron comes in between
and Cu is least reactive of them : )