The product gas from a solid fuel combustion reaction has the following dry-basis molar composition: 72.0%CO₂, 2.57%CO, 0.0592% SO₂, and 25.4%O₂. Pure oxygen is fed to the furnace in 20% excess of that required to burn the fuel completely. There is no oxygen in the fuel. Calculate the elemental composition (mole% of the various elements) of the fuel, stating any assumptions you have to make to arrive at your answer.