A gaseous fuel with a volumetric analysis of 60 percent CH4, 30 percent H2, and 10 percent

Question:

A gaseous fuel with a volumetric analysis of 60 percent CH4, 30 percent H2, and 10 percent N2 is burned to completion with 130 percent theoretical air. Determine
(a) The air–fuel ratio and
(b) The fraction of water vapor that would condense if the product gases were cooled to 20°C at 1 atm.