On the average, the temperature of the earth's crust increases 1.0 Co for every 30 m of depth. The average thermal conductivity of the earth's crust is 0.74 J/m ∙ s ∙ K. What is the heat loss of the earth per second due to conduction from the core? How does this heat loss compare with the average power received from the sun? (The solar constant is about 1.35 kW/m2)