A firm is considering an investment in a new machine with a price of $10.9 million to replace its existing machine. The current machine has a book value of $3.8 million and a market value of $2.8 million. The new machine is expected to have a four-year life, and the old machine has four years left in which it can be used. If the firm replaces the old machine with the new machine, it expects to save $4.4 million in operating costs each year over the next four years. Both machines will have no salvage value in four years. If the firm purchases the new machine, it also will need an investment of $250,000 in net working capital. The required return on the investment is 10% and the tax rate is 21%. The company uses straight-line depreciation. What are the NPV and IRR for both possible decisions?

PLEASE show all work in excel so I can follow along. I'm especially curious as to whether or not the salvage value of the old machine factors in as a gain at T0 for the layout of the new machine. Similarly, does the salvage value factor in as a negative on the layout of the old machine due to opportunity cost?