In batteries and fuel cells,which energy is converted into which energy?

Assertion : If $\lambda^o_{Na^{+}}$ and $\lambda^o_{Cl^{-}}$ are molar limiting conductivity of sodium and chloride ions respectively,then the limiting molar conductivity for sodium chloride is given by the equation :
$\Lambda^o_{NaCl} = \lambda^o_{Na^{+}} + \lambda^o_{Cl^{-}}$
Reason : This is according to Kohlrausch law of independent migration of ions.

In the reaction $Cu_{(s)} + 2Ag^{+}_{(aq)} \to Cu^{2+}_{(aq)} + 2Ag_{(s)}$,the reduction half-cell reaction is:

In a Mercury cell,which of the following acts as a cathode?

Which of the following statements is true about the voltaic cell?

Given that $\frac{1}{3} \lambda_m^\infty (Fe^{3+}) = 68 \ \Omega^{-1} \ cm^{2} \ eq^{-1}$ and $\frac{1}{2} \lambda_m^\infty (SO_4^{2-}) = 80 \ \Omega^{-1} \ cm^{2} \ eq^{-1}$. What will be the value of $\lambda_{eq}^\infty (Fe_2(SO_4)_3)$? ............ $\Omega^{-1} \ cm^2 \ eq^{-1}$