Baker's Delight offers a special promotion on Thursdays where customers can buy one loaf of bread and get another one for free. The bakery opens at 9am, but customers start lining up at 8:30am. Customers arrive at a rate of 30/hr until 10am and then at a rate of 20/hr until 12pm. The bakery can bake bread serve the customers at a rate of 25/hr, and the counter works till all customers served. (a) Draw the Inventory Build-Up diagram showing the number of customers waiting in line in 30-minute time slots. Start the graph at 8:30am and show the number of waiting customers until the line becomes empty. Use discrete time setting. (b) Using the inventory build-up diagram, calculate the average number of customers in line. (c) How long on average does a customer spend in line? (Hint: Littles Law. You need to compute average throughput rate first. Pay attention to units.)