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Wiley E. Coyote is planning to install movement sensors in different locations in an effort to capture his nemesis Road Runner. He selects locations Road Runner always visits. Each sensor is advertized to have an effective range of 175 yards and costs $75. The following table shows distance between locations. Poor Wiley has only $400 and hence wants to minimize the number of sensors to install and yet cover all of the locations. (a) How many sensors can Wiley buy? What is the total cost of these sensors? Give a complete model to the problem in the space below. Next solve the model in Excel, save the spreadsheet, and report the answer here. (b) After a few failed attempts, Wiley used his knowledge of statistics to prove that the sensors actually have an effective range of only 130 yards. Assuming that he will use the sensors bought in the previous problem, how many additional sensors will he need now