please help i am at my last attempt

Tamarisk Unlimited is considering purchasing an additional delivery truck that will have a seven-year useful life. The new truck will cost $33,000. Cost savings with this truck are expected to be $9,800 for the first two years, $7,200 for the following two years, and $3,000 for the last three years of the truck's useful life. What is the payback period for this project? (Round answer to 2 decimal places, e.g. 52.75.) Payback period years What is the discounted payback period for this project with a discount rate of 8 percent? (Round intermediate calculations to 5 decimal places, e.g. 0.42355. Round answer to 2 decimal places, e.g. 52.75.) Discounted payback period years