Outdoor air enters an ac unit at 10℃ and 35 % relative humidity at a steady rate of 17 m3⁄ and it leaves at 25℃ and 65 % relative humidity. the outdoor air is first heated to 22℃ in the heating section and then humidified by the injection of hot steam in the humidifying section. assuming the entire process takes place at a pressure of 1 , determine (a) the rate of heat supply in the heating section and (b) the mass flow rate of steam required in the humidifying section.