Problem 3. Your company is considering the installation of a computer system at the cost of $250,000. This system's service life is eight years. It has no salvage value at the end of the service life. This system will result in followings: 1) Increase sales revenue $40,000 per year. 2) Save operation cost $120,000 per year. 3) Increase maintenance cost $50,000 per year. The annual incomes and expense occur at the end of each year, MARR is 12% per year compound weekly. 1 yr = 52 wk. a) Calculate the payback period in years. b) Calculate the present worth of profit