Write an equation for combustion of methane?

Classify the following unbalanced half equations as oxidation and reduction.

Oxidation numbers of $\mathrm{Cl}$ atoms marked as ${\mathrm{Cl}}^{\mathrm{a}}$ and ${\mathrm{Cl}}^{\mathrm{b}}$ in ${\mathrm{CaOCl}}_2$ (bleaching powder) are

${\mathrm{Ca}}_{\setminus \mathrm{O}-{\mathrm{Cl}}^{\mathrm{b}}}^{{/}^{{\mathrm{Cl}}^{\mathrm{a}}}}$

The coefficients $\mathrm{p}, \mathrm{q}, \mathrm{r}, \mathrm{s}$ in the reaction $\mathrm{p} {\mathrm{Cr}}_2{{\mathrm{O}}_7}^{2-}+\mathrm{q} {\mathrm{Fe}}^{2+}+14{\mathrm{H}}^{+}\to \mathrm{r} {\mathrm{Cr}}^{3+}+\mathrm{s} {\mathrm{Fe}}^{3+}+7{\mathrm{H}}_2\mathrm{O}$ respectively are :

For the following redox reactions, find the correct statement.

${\mathrm{Sn}}^{2\oplus }+ 2{\mathrm{Fe}}^{3\oplus }\to {\mathrm{Sn}}^{4\oplus }+2{\mathrm{Fe}}^{2\oplus }$