Ethane (C2H6) at 20°C and 200 kPa and methane (CH4) at 45°C and 200 kPa enter an adiabatic mixing chamber. The mass flow rate of ethane is 9 kg/s, which is twice the mass flow rate of methane. Determine (a) the mixture temperature and (b) the rate of entropy generation during this process, in kW/K. Take T0 = 25°C.