Hello please feel out this workbook/excel sheet. Don't forget to provide explanation on the calculations made. You can find the excel sheet at this link:

https://docs.google.com/spreadsheets/d/1R7uBGRN30E8hu8eU1iHSMjiki-Un2qpd/edit?usp=sharing&ouid=109841440177232783905&rtpof=true&sd=true

Hint for the workbook:

In table 2, for year 1, for the projected after tax cash flow, it is -22.9 +23.9 - (-4.8) - (-1.8) = $7.6. For the year 1, for the PV column, I suggest =PV(6%,1,,7.6) which is $7.2 (where the 1 is the value for the year). For reference, the year 2 projected after tax cash flow is $65.1 and the PV for year 2 is $57.9. At the bottom of the PV column, simply sum the eight values above it. The NPV is the latter value and subtract the year 0 value (191.1) from it. You can fill in this same number for NPV1 to the right of it in the table. For the NPV2 column, it is similar; for year 1 =PV(4.95%,1,,7.6) which is $7.3. The only difference for this column is the discount rate of 4.95%.

In the last table on tab 2, in the discounted cash flow row, the values in the PV column should be placed there. This is because "discounted" indicates they have been adjusted using the discount rate. Thus, year 0 is -191.1, year 1 is 7.2, year 2 is 57.9, etc. For the cumulative discounted cash flows row, for year 0 it is -191.1, year 1 is -183.9 (-192.1 + 7.2), year 2 is -126.0 (-183.9 + 57.9), etc. This very last row will show where the actual payback time is. It is at that place where the cumulative value becomes positive. It does break evenly but you will easily see within the row in what year it becomes positive.