A coal analyzing $($by weight$)65\mathrm{.}4\%C,5\mathrm{.}3\%H,0\mathrm{.}6\%S,1\mathrm{.}1\%N,18\mathrm{.}5\%O,$ and $9\mathrm{.}1\%$ ash is burned so that all combustible is burned out of the ash. The flue gas analyzes $($by mole$)13\mathrm{.}00\%C{O}_2$ and $S{O}_2,0\mathrm{.}76\%CO,6\mathrm{.}17\%O_2,0\mathrm{.}87\%H_2,$ and $79\mathrm{.}20\%N_2.$ Calculate

a$.$ Pounds of coal fired per $100$lbmol of dry flue gas

b$.$ Ratio of moles of total combustion gases to moles of dry air supplied

c$.$ Total moles of water vapor in the stack gas per $100l{b}_m$ of coal if the entering air is dry

d$.$ Percent excess air