An investment project costs $16,800 and has annual cash flows of $3,500 for 6 years. If the discount rate is zero percent, the discounted payback period is _________ years. If the discount rate is 5 percent, the discounted payback period is _________ years. If the discount rate is 19 percent, the discounted payback period is __________ years. (Enter 0 when there is no payback period. Round your answers to 2 decimal places (e.g., 32.16))