please help me just re do it i think its right just want to make sure

Kevin, a calendar-year taxpayer, utilizes the cash method of accounting for his small business, which provides various consulting expertise to the railroad industry. At the end of the year, he spent significant time working on a consulting project for Regional Railroad's light rail replacement initiative. Although the project is not done, Regional Railroad's project manager knows Kevin spent a significant amount of time and wants to get Kevin paid before year-end. As such, he told Kevin he may issue a progress billing for time incurred to date. However, Kevin expects the project to wrap up within the first week of the new year, and is concerned of the tax implications of including the income on his current year tax return. Kevin has asked his nephew, a tax consultant, for some advice. Kevin has spent 120 hours on the project to date with a billing rate of $100/ hour; his after-tax rate of return is 12% and his marginal tax rate is 28%. \begin{tabular}{|c|c|c|c|c|c|c|c|} \hline & A & B & C & D & E & F & G \\ \hline 10 & & & & & & & \\ \hline 11 & Required: & & & & & & \\ \hline 12 & 1. Prepare a Present Value Comp & rmulas & & & & & \\ \hline 13 & & & & & & & \\ \hline 14 & (HINT: Do not enter an amo & he PV formula as there & are no cash flows in & wi & bil & ad, & \\ \hline 15 & & & & & & & \\ \hline 16 & & Comparison & & & & & \\ \hline 17 & Description & Option1:ReceivePaymentBefore12/31 & Option2:ReceivePaymentAfter12/31 & & & & \\ \hline 18 & Time Incurred (hours) & 120.00 & 120.00 & & & & \\ \hline 19 & Hourly Billing Rate & $100.00 & $100.00 & & & & \\ \hline 20 & Taxable Income & $12,000.00 & $12,000.00 & & & & \\ \hline 21 & Marginal Tax Rate & 28% & 28% & & & & \\ \hline 22 & Tax Liability & $3,360.00 & $3,360.00 & & & & \\ \hline 23 & Present Value Tax Liability & $3,000.00 & $3,000.00 & & & & \\ \hline 24 & After-tax Cash Flow & & & & & & \\ \hline 25 & Before-tax income & $12,000.00 & $12,000.00 & & & & \\ \hline 26 & Less: Present Value Tax Liability & $3,000.00 & $3,000.00 & & & & \\ \hline 27 & After-tax cash flow & $9,000.00 & $9,000.00 & & & & \\ \hline 2829 & & & & & & & \\ \hline 30 & & & & & & & \\ \hline \end{tabular}