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Grand Construction Co. is considering a new inventory system that will cost $750,000. The system is expected to generate positive cash flows over the next four years in the amounts of $350,000 in year one, $225,000 in year two, $150,000 in year three, and $180,000 in year four. Grand's required rate of return is 8%. For all questions enter a number with 2 decimals. a D years a. The payback period of this project is b. The discounted payback period of this project is years. The net present value of this project is $ d. The profitability index of this project is H. The internal rate of return of this project is % 1. The modified internal rete of return of this project assuring the reinvestment rate of 9% is