Air is humidified with the dry bulb temperature remaining constant. Wet steam is supplied for humidification at 20 psia (138 kPa). If the air is at 80 F (32 C) db, 60 F (16 C) wb, and sea-level pressure, what quality must the steam have (a) to provide saturated air and (b) to provide air at 70 percent relative humidity?
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