Moist air at 95°F, 1 atm, and a relative humidity of 30% enters a steam-spray humidification device operating at steady state with a volumetric flow rate of 5700 ft3/min. Saturated water vapor at 230°F is sprayed into the moist air, which then exits the device at a relative humidity of 50%. Heat transfer between the device and its surroundings can be ignored, as can kinetic and potential energy effects. Determine
(a) the temperature of the exiting moist air stream, in °F.
(b) the rate at which steam is injected, in lb/min.