can someone explain how to do this

Cash payback period for a Service Company Prime Financial Inc. is evaluating two capital investment proposals for a drive-up ATM Kiosk, each requiring an investment of $175,000 and each with an eight- year life and expected total net cash flows of $280,000. Location is expected to provide equal annual net cash flows of $35,000, and Location 2 is expected to have the following unequal annual net cash flows Year 1 $68,000 Year 5 537,000 Year 2 51,000 Year 6 29,000 Year 33,000 Year 21,000 Year 4 23,000 Year 8 18,000 Determine the cash payback period for both location proposals Location 1 5 years Location 2 4 years