$E^o_{Ag^+/Ag}=0.79$volt
$E^o_{NO_3^-/NO}=1$volt
$E^o_{NO_3^-/NO_2}=0.82$volt
$298\large\frac{RT}{F}$$=0.06$volt
$P_{NO_2}=P_{NO}=10^{-3}$
T=298K
$[Ag^+]=0.2M$
$[HNO_3]=1.5M$
$\begin{array}{1 1}(a)\;0.24v\\(b)\;0.25v\\(c)\;0.3v\\(d)\;0.27v\end{array}$