Ambient air at $100 \mathrm{kPa}, 30^{\circ} \mathrm{C}, 40 \%$ relative humidity goes through a constant-pressure heat exchanger as a steady flow. In one case it is heated to $45^{\circ} \mathrm{C},$ and in another case it is cooled until it reaches saturation. For both cases, find the exit relative humidity and the amount of heat transfer per kilogram of dry air.