Which following reagent is used in Etard reaction?

Which of the following processes exhibits increase in internal energy?

Calculate $$\mathrm{E}_{\text {cell }}^0$$ if the equilibrium constant for following reaction is $$1.2 \times 10^6$$.

$$2 \mathrm{Cu}_{(\mathrm{aq})}^{+} \longrightarrow \mathrm{Cu}_{(\mathrm{aq})}^{++}+\mathrm{Cu}_{(\mathrm{s})}$$

Which from following alloys is used to make statues?