Organilk has a large milk-processing plant producing organic dairy products such as cheese, creams, and different types of pasteurized milk. The plant works from 7:00 am to 4:00 pm. There are 72 trucks that bring milk from farms to Organilk. They arrive at the plant starting from 7:00 am to 1:00 pm at almost a constant rate of 12 trucks per hour. Each truck brings a full tank of milk which is around 5000 gallons (a total of 72 x 5000 = 360,000 gallons). Milk is then unloaded into the outdoor tanks to be used by the processing plant. Outdoor tanks have a total capacity of storing 50,000 gallons of milk. The unloading process is very fast, if the space is available in outdoor tanks. If outdoor tanks are full, trucks cannot be unloaded and they must wait until space becomes available in outdoor tanks. After unloading a truck, the truck leaves the plant. The plant has the capacity of processing 40,000 gallons of milk per hour, which are taken directly from outdoor tanks. The plant starts processing at 7:00 am when the first truck arrives and works until it finishes processing all 360,000 gallons of milk delivered on the same day. Use the continuous approximation of inventory curve and find the answers to the following questions: a. When does the queue of trucks begin to build? b. What is the maximum number of trucks waiting in the queue to unload their milk? c. What is the average gallons of milk waiting in the tanks or in the trucks? d. How many of the 72 trucks end up waiting and what is the average waiting time for those trucks?