In the extraction of zinc,what burns to produce a blue flame?

The chemical processes in the production of steel from haematite ore involve

Out of $C$ and $CO$,which is a better reducing agent for $ZnO$?

In the blast furnace,the reduction of iron oxide is carried out by which of the following?

In the electrolytic extraction of aluminum,molten cryolite $(Na_3AlF_6)$ is used to:

Observe the following statements:
Statement-$I$: The choice of reducing agent for the reduction of an oxide ore can be predicted by using Ellingham diagram,a plot of $\Delta G^{\ominus}$ vs $T$.
Statement-$II$: According to Ellingham diagram,metal oxide with higher $\Delta G^{\ominus}$ is more stable than the oxide with lower $\Delta G^{\ominus}$.