Hi all! For this question's part (a), I initially thought that I should first apply the first law for control volume for the system of the evaporator so that the rate of heat transfer from the evaporator to the air can be found. Then apply first law again on the air with using the specific heat to find out the exit temperature. Does this method sound? It seems that I'm doing part(b) before part (a)... What should be the more appropraite method?