Which among the following is CORRECT formula for determination of cell constant?

What happens when solution of an electrolyte is diluted?

Calculate $$E_{\text {cell }}^{\circ}$$ in which following reaction occurs. $$\mathrm{Mg}_{(\mathrm{s})}+2 \mathrm{Ag}_{(\mathrm{IM})}^{+} \rightarrow \mathrm{Mg}_{(1 \mathrm{M})}^{+}+2 \mathrm{Ag}_{(\mathrm{s})}$$ if $$\mathrm{E}_{\mathrm{Ag}}^{\circ}=0.8 \mathrm{~V}$$ and $$\mathrm{E}_{\mathrm{Mg}}^{\circ}=-2.37 \mathrm{~V}$$

Calculate the conductivity of $$0.02 \mathrm{~M}$$ electrolyte solution if its molar conductivity $$407.2 \Omega^{-1} \mathrm{~cm}^2 \mathrm{~mol}^{-1}$$ ?