[2] (a) Using the information given in Problem 17 and the known distance from the Earth to the sun (1.5 X 10" m), calculate the total power that the sun radiates into space. (b) There are about 10" stars like the sun in the Milky Way galaxy, and 10" galaxies in the universe. Use this information to estimate the rate at which the entropy of the universe is increasing, assuming that the average temperature of the universe is 2.73 K. real world