A consulting engineering firm is considering two models of SUVs for the company principals. A GM model will have a first cost of $36,000 an oerating cost of $4000, and a salvage value of $15,000 after 3 years. A Ford model will have a first cost of$32,000, and operating cost of $31000, and also have a $15,000 resale value, but after 4 years. a) At an interest rate of 15% per year, which model should the consulting firm buy? Conduct an annual worth analysis b) What are the PW values for each vehicle?