The human body converts internal chemical energy into work and heat at rates of 60 to 125 W (called the basal metabolic rate). This energy comes from food and is usually measured in kilocalories [1 kcal = 4.186 kJ]. (Note that the nutritional `Calorie' listed on packaged food actually equals 1 kilocalorie). How many kilocalories of food energy does a person with a metoblic rate of 91.0 W require per day? (Assume 100 percent efficiency.)