A fast-food restaurant makes hamburgers on a grill. At any given time, only four hamburgers can fit on the grill. If there is no room on the grill, the customers are asked to order a different item. Assume that the time between hamburger orders and the cook time of hamburgers are both exponentially distributed. Furthermore suppose that, on average, one customer asks for a hamburger every five minutes, and it takes an average of 8 minutes to cook a hamburger. Construct the rate diagram for this CTMC. Make sure to clearly define your states.