please explain how you got your answers and not in excel

Morrison Industries is evaluating whether to invest in solar panels to provide some of the electrical needs of its main office building in Green Bay, Wisconsin. The solar panel project would cost $500,000 and would provide cost savings in its utility bills of $75,000 per year. It is anticipated that the solar panels would have a life of 20 years and would have no residual value. Read the requirements. (Click the icon to view the present value factor table.) (Click the icon to view the present value annuity factor table.) (Click the icon to view the future value factor table.) (Click the icon to view the future value annuity factor table.) Requirement 1. Calculate the payback period in years of the solar panel project. Determine the formula, then calculate the payback period. (Round your answer to two decimal places.) Initial investment Expected annual net cash inflow Payback period 500,000 75,000 6.67 years Requirement 2. If the company uses a discount rate of 12%, what is the net present value of this project? (Round your answer to the nearest whole dollar. Use parentheses or a minus sign for a negative net present value.) The net present value of the project is