An ideal gas mixture has the following partial pressures and components: CO2, 20 kPa; O2, 30 kPa; N2, 30 kPa; and CH4 at 20kpa. Determine the mole fractions and mass fractions of each component. Calculate the apparent molar mass, the apparent gas constant, the constant-volume specific heat, and the specific heat ratio at 300 K for the mixture.