An investment project has annual cash inflows of $2,800, $3,700, $5,100, and $4,300, for the next four years, respectively. The discount rate is 11 percent. a. What is the discounted payback period for these cash flows if the initial cost is $5,200? (Do not round intermediate calculations and round your answer to 2 decimal places, e. g., 32.16.) b. What is the discounted payback period for these cash flows if the initial cost is $6,400? (Do not round intermediate calculations and round your answer to 2 decimal places, e. g., 32.16.) c. What is the discounted payback period for these cash flows if the initial cost is $10,400? (Do not round intermediate calculations and round your answer to 2 decimal places, e. g., 32.16.)