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 receive from the Sun. Assume also that the surface of the Earth is at a Constant temperature over the day-night cycle. Use Tθ = 5800 K; Rθ = 7 × l010 cm: arid the Earth-sun distance of 1.5 × 1013 cm