A fuel consisting of only C and H atoms is fed to a warship engine. In the engine reactor, this fuel is burned with excess air. The input flow that is coming to the reactor has the fuel and excess air. The product that is coming out from the engine reactor has the following mole percents; $20\%$ carbondioxide, $10\%$ carbonmonoxide, $20\%$ oxygen, $25\%$ nitrogen and $25\%$ water. Draw and label a flowchart and do the degree$-$of$-$freedom analysis. Calculate the unknown variables.