A waste gas stream from a plant is disposed of by burning it in a flare with air. The waste gas has the following composition:

Orsat analysis of the off-gas reveals 0.3% sulfur dioxide, plus carbon dioxide, oxygen, and nitrogen. Calculate the percentage of excess air and the composition of all streams. Explain each calculation in detail.

\begin{tabular}{cccc} \hline Substance & Composition(%mol) & Substance & Composition(%mol) \\ \hline Methane & 30 & Oxygen & 2 \\ Carbon dioxide & 10 & Hydrogen sulfide & 2 \\ Carbon monoxide & 8 & Water & 2 \\ Hydrogen & 10 & Nitrogen & 36 \\ \hline \end{tabular}