pls help with the right formula. really struggling with this. everybodyvwlse is just copying and pasting wrong answers. thanks in advance

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 vear, 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%