The standard cell potential for the cell `Zn|Zn^(2+) (1 M)|| Cu^(2+) (1 M)| Cu`
given `E_(Cu^(2+)//Cu)^(@) = 0.34 V`
and `E_(Zn^(2+)//Zn)^(@) = - 0.76 V` is

Explanation

`2 Ag^(+) (aq) + Cu (s) to 2 Ag (s) + Cu^(2+) (aq)`
`Cu |Cu^(2+) (aq) || Ag^(+) (aq) |Ag`
`E_(cell)^(Theta) = E_((Ag^(+)|Ag))^(Theta) - E_((Cu^(2+)|Cu))^(Theta)`
`= 0.80 - 0.34`
`=0.46 V`
`therefore` Reaction is fesaible.