As a general rule, a moderately active male adult needs a number of nutritional Calories per day equal a 18 times his weight in pounds. The heat of combustion of typical fatty acid is about 7Kcal/g. If a 150 pound man eats 2000 Calories per day. How long will it take him to lose 10 pounds? Note that the calorie equals one ordinary kilocalorie. Assume that all weight loss is due to fat loss