Please answer all question in Part A

Part A Explain the causes of incomplete combustion. Which is more likely to be found in the products of an incomplete combustion of a hydrocarbon fuel, co or OH? Why? Are complete combustion and theoretical combustion identical? If not, how do they differ? Consider a fuel that is burned with (l) 130% theoretical air and (ii) 70% excess air. In which case is the fuel burned with more air