Find out the discounted payback period

Question

Problem:

An investment project costs $10,000 and has annual cash flows of $2,970 for six years.

• What is the discounted payback period if the discount rate is zero percent?
• What is the discounted payback period if the discount rate is 6 percent?
• What is the discounted payback period if the discount rate is 20 percent?

Note: Provide support for your rationale.