A water-cooling tower for a power plant cools 45°C liquid water by evaporation. The tower receives air at 19.5°C, ϕ = 30%, 100 kPa that is blown through/over the water such that it leaves the tower at 25°C, ϕ = 70%. The remaining liquid water flows back to the condenser at 30°C having given off 1 MW. Find the mass flow rate of air, and the amount of water that evaporates.