What is the sign of $\Delta G^o$ and the value of $K$ for an electrochemical cell for which $E_{cell}^o = 0.80 \ V$?

For a redox reaction,$Oxi + ne^- \rightarrow Red$,what is the correct form of the Nernst equation?

Calculate the cell potential for $Ni_{(s)} | Ni^{2+}(0.036 \ M) || Co^{2+}(0.018 \ M) | Co_{(s)}$ at $298 \ K$.

Which graph correctly correlates $E_{cell}$ as a function of concentrations for the cell (for different values of $M$ and $M'$):-
$Zn_{(s)} + Cu^{2+}(M) \to Zn^{2+}(M') + Cu_{(s)};$ $E^o_{cell} = 1.10 \, V$
$X$-axis : $log_{10} \frac{[Zn^{2+}]}{[Cu^{2+}]}$,$Y$-axis : $E_{cell}$

If $E^{\circ}(Zn_{(aq)}^{+2} \mid Zn_{(s)}) = -0.76 \ V$,calculate the potential for $Zn_{(s)} \rightarrow Zn_{(0.01 \ M)}^{+2} + 2e^{-}$ at $298 \ K$.

The photoelectric current from $Na$ (work function,$w_{0}=2.3 \ eV$) is stopped by the output voltage of the cell
$Pt_{(s)} | H_{2}(g, 1 \ bar) | HCl(aq, pH=1) | AgCl_{(s)} | Ag_{(s)}$
The $pH$ of aqueous $HCl$ required to stop the photoelectric current from $K$ $(w_{0}=2.25 \ eV)$,all other conditions remaining the same,is..........$\times 10^{-2}$ (to the nearest integer).
Given,$2.303 \frac{RT}{F}=0.06 \ V; E_{AgCl|Ag|Cl^{-}}^{0}=0.22 \ V$