A man eats a dessert that contains 170 Calories. (1 Calorie = 4186 J) The skin temperature of the man is 37.4 °C and that of her environment is 20.8 °C. The emissivity of her skin is 0.78 and its surface area is 1.3m2. Find how many hours would it take her to emit anet radiant energy from her body that is equal to the energy contained in this dessert?