Consider the following two gas-phase reactions: A+B C 2C D The equilibrium constants of the two reactions are given by, K, =- a a, yaP %3D K. Where y, indicates the mole fraction defined as Nj / Nr and Nr is the total mumber of moles. What are the two equilibrium equations relating the two unknown extents of reaction (X1 and X2) and the initial gas-phase compositions (y;o)? You can assume the pressure is low enough and the gases are ideal.