Can I get some help on this problem, please?

Debra just graduated from college. Since she is starting her own business, it's time to upgrade from her clunker to a reliable vehicle. Debra has the option to purchase a new car for her business at a cost of $21,606 (life of 7 years with no salvage value), estimating that it would help her bring in additional annual net operating cash flows of $7,800 over the life of the car. Determine the simple payback period and the IRR for this investment. Debra expects her business income to be subject to a 30% tax rate. (Round simple payback period to 3 decimal places, e.g. 15.256 and IRR to 2 decimal places, e.g. 15.25%. Round intermediate calculations to 2 decimal places, e.g. 15.25.) Simple payback period years IRR %