How do we calculate incremental free cash flow and NPV please provide the answer along with formula and clear steps??

Project Beta is a project which will last for 7 years and which requires an initial outlay of $4,000. This outlay will be depreciated using straightline depreciation over the life of the project. It will generate incremental revenue of $1600 per year. The value of incremental, aftertax eamings is $533 per year. The project will require Net Woming Capital equal to 15% of incremental revenue. What is the value of incremental free cash ow in Years 1 to 7'? A project has the cash flows shown in the following table. If the cost of capital is 12%, what is the NPV of the project? Year Incremental Free Cash Flow =86? 305