You also allow professors to come to your stand during exam week and you give them priority over students when ordering. For the sake of the simulation, you can assume professors have a priority of 90 and students have a priority of 20. In this case, professors come in pairs of 2 at an exponential rate with a mean of 10 minutes. Professors don't need to prepare for exams so they leave immediately after being served. You can assume queues have infinite capacities. The model includes variables to track inventory (e.g. Water_Inventory, Pepsi_Inventory, Coffee_Inventory) and shortages (e.g. Water_Shortage, Pepsi_Shortage, Coffee_Shortage). Assume that if you run out of any of your drinks, you lose the sale (e.g. the student/professor won't buy any other drink). Students may still go to the lounge even if they didn't buy a drink