P9-15 Calculating Profitability Index [LO7) Year 0 1 2 3 Cash Flow -$7,900 4,500 4,800 3,700 a. What is the profitability index for the cash flows if the relevant discount rate is 8 percent? b. What is the profitability index for the cash flows if the relevant discount rate is 20 percent? c. What is the profitability index for the cash flows if the relevant discount rate is 24 percent