A fuel has a composition by weight of $0\mathrm{.}865$ carbon, $0\mathrm{.}133$ hydrogen and $0\mathrm{.}002$ incombustibles. Find the stoichiometric air$/$fuel ratio.

When the fuel is burnt with excess air, the dry volumetric exhaust gas analysis is: $C{O}_2$:$0\mathrm{.}121$;$N_2$:$0\mathrm{.}835,O_2$:$0\mathrm{.}044$

Determine the actual air$/$fuel ratio used and the wet volumetric exhaust gas analysis.