An ancient internal combustion Mugwump bilge-pump engine burns a mixture of obscure hydrocarbon fuels that can be modeled as a single fuel. An Orsat analysis of the dry exhaust gas from this engine gives the following results: 5.90% CO₂, 5.50% CO, 7.50% O₂, and 81.1% N₂. Determine

a. The single fuel hydrocarbon model (C_nH_m).

b. The carbon and hydrogen composition by mass of this fuel.

c. The percent of theoretical air used in the engine.