Standard reduction potential of Ag+/Ag couple has value higher value, hence, it will act as cathode and Cu2+/Cu will act as anode.
Thus, the cell representation will be,
Cu(s)∣Cu2+(aq, 4.0 M)∥Ag+(aq, 0.1 M)∣Ag(s)
Cell reaction is
Cu+2Ag+→Cu2++2Ag
Here n = 2;
E = E0cell − 0.0592log[Cu2+][Ag+]2
E0cell=E0cathode−E0anode
E0cell=0.80−0.34
E0cell=0.46 V
By Nernst equation,
Ecell=0.46 − 0.0592log[4.0][0.1]2
Ecell= 0.46 − 0.0592 log (4 × 102)
Ecell= 0.46 − 0.0592×0.602−0.059
Ecell= 0.46 − 0.018−0.059
Ecell= 0.46 − 0.077
Ecell= 0.383 V