(note: dollar values have been changed from the problem in the book, which appears to have been written in something like 1974). You are given the following information about a dry-batch paving operation. You are going to use one mixer that has a service rate of 30 services per hour (meaning: it can fill 30 mixing trucks each hour). The dry-batch trucks you use for bringing concrete to the paver have an arrival rate of 7.5 arrivals per hour at the plant. That means that a single truck would complete 7.5 cycles (plant loading + transit to paver + unload at the paver + return to the plant) in an hour. Each truck carries 6 cubic yards of concrete. You have a total amount of 13,500 CY of concrete to pour. You rent a truck at $100/hr and the paver at $300/hr. If the job takes more than 80 hours, you pay a penalty of $700/hr owing to delays in job completion. On the basis of least cost, determine the number of trucks you should use. Plot the cost versus the number of trucks used