Helium at 200 kPa, 20oC is heated by mixing it with argon at 200 kPa, 500oC in

Question:

Helium at 200 kPa, 20oC is heated by mixing it with argon at 200 kPa, 500oC in an adiabatic chamber. Helium enters the chamber at 2 kg/s and argon at 0.5 kg/s. If the mixture leaves at 200 kPa, determine
(a) The temperature (T2) at the exit
(b) The rate of entropy generation (Sgen) due to mixing.