Calculate the standard cell potential (in V) of the cell in which following reaction takes place :
$$
\mathrm{Fe}^{2+}(\mathrm{aq})+\mathrm{Ag}^{+}(\mathrm{aq}) \rightarrow \mathrm{Fe}^{3+}(\mathrm{aq})+\mathrm{Ag}(\mathrm{~s})
$$
Given that
$$
\begin{aligned}
& \mathrm{E}_{\mathrm{Ag}^{+} / \mathrm{Ag}}^0=\mathrm{xV} \\
& \mathrm{E}_{\mathrm{Fe}^{2+/ \mathrm{Fe}}}^0=\mathrm{yV} \\
& \mathrm{E}_{\mathrm{Fe}^{3+/ \mathrm{Fe}}}^0=\mathrm{zV}
\end{aligned}
$$
