Star a Has a Radius of 200 000 Km and a Surface

Question 69
Essay

Star A has a radius of 200 000 km and a surface temperature of 6 000 K.Star B has a radius of 400 000 km and a surface temperature of 3 000 K.The emissivity of both stars is the same.What is the ratio of the rate of energy radiated by Star A to that of Star B?