In Finance, the discounted payback period in 3.5 because the company has a cost capital of 8%, is that correct?

GoFlo is a small growing firm that is considering the purchase of another truck to serve GoFlo's expanding customer base . The new truck will cost $21 000 and should generate annual net cash flows of $6 000 over the truck's 5 - year life . What is the discounted payback period for this project if the company has a cost of capital of 8 7 3 years 4 . 28 years 3 . 3 years 3.5 years