(a) Determine the air-fuel ratio on mass basis (b) Determine the percentage theoretical air used (c) Determine the equivalence ratio 1. (20 pts) Methane (CH4) is burned with simple air.

The volumetric analysis of the products on a dry basis is 5.20% \mathrm{CO}_{2}, 0.33 \% \mathrm{CO}, 11.24 \% \mathrm{O}_{2}, \text { and } 83.23 \% \mathrm{~N}_{2}