Which cell differs from the fundamental principle point of view?

For the decomposition of $Al_2O_3$ at $500\,^{\circ}C$,the Gibbs energy change is given by $\frac{2}{3} Al_2O_3 \rightarrow \frac{4}{3} Al + O_2$,$\Delta G = 966 \, kJ \, mol^{-1}$. What is the potential difference (in $V$) required for the electrolytic reduction of $Al_2O_3$ at $500\,^{\circ}C$?

The reaction at the cathode in the cells commonly used in clocks involves:

In which of the following cells,the space between cathode and anode is filled by a moist mixture of ammonium chloride and zinc chloride?

When a lead storage battery is charged:

If less than $1.1 \ V$ external opposite current is passed through the Daniell cell,for such condition answer the following questions :
$(1)$ Give reaction of cathode,anode and redox.
$(2)$ Between $Zn$ and $Cu$ which metal dissolve in solution ?