4-20 Solar radiation is incident on a flat-plate collector at a rate of 880 W/m?. The product of the transmissivity of glazing and the absorptivity of absorber plate is 0.82.

The collector has a surface area of 33 m?. This collector supplies hot water to a facility at a rate of 6.3 L/min. Cold water enters the collector at 18°C. If the efficiency of this collector is 70 percent, determine the temperature of hot water provided by the collector.