Question 4 [35 points]: A postal service worker loads the packages to delivery car for the next day delivery. The worker picks up the packages from the ground and put it to back of the delivery truck whose dock height is 36". He loads on average 500 packages per hour where each package weighs 25 lbs. a. Determine the total energy expenditure of this worker at the end of an 8-hour shift. b. What is the grade of his work? c. Determine the rest allowance for this task if the worker works 15 minutes uninterrupted. d. How much rest would be required for 1 hour of work