Rob, a young engineer, notices that, over a long period of time, he has added 20.0 lbm (9.07 kg) of excess body fat and decides to lose this extra weight by dieting alone. Rob's activities are such that his caloric intake and energy output are identical. He normally eats two of the following meals per day, seven days per week: one cheeseburger, one regular fries, and one 10.0 oz cola. Also, he consumes 2.00 MJ per day of snack food while working. How long will it take him to lose the extra 20.0 lbm of body fat by
a. Eliminating the daily snack food only?
b. Eliminating the daily snack food plus eating only one of these meals per day?
c. Going on a total starvation diet with no food whatsoever being consumed?