Calculate the temperature of the surface of the earth on the assumption that as a black body in thermal equilibrium it reradiates as much thermal radiation as it receives from the sun. Assume also that the surface of the Earth is at a constant temperautre over the day-night cycle. Use T=5800K; R= 7 x 10¹⁰ cm; and the Earth-Sun distance of 1.5 x 10¹³cm.
