Please give a detailed explaination

A Company is contemplating the replacement of an old machine with newer and more efficient one. The old machine has a book value of $350,000 and a remaining useful life of 4 years. The firm expects to sell this old machine for $100,000 in 4 years, but also it can sell it now to another firm in the industry for $350,000. The old machine is being depreciated by $87,500 per year using the straight-line method. The new machine has a purchase price of $750,000 and requires $50,000 transportation and shipping expenses. The new machines falls into MACRS class of 3 years, (MACRS 3-years rates are 33%, 45%, 15% and 7%. This machine can be sold for $50,000 at the end of 4 years from now in the market. The machine is expected to economize on electric power usage, labor, and repair costs. In total, an annual savings of $275,000 will be realized if the new machine is installed. The company's marginal tax rate is 25%, and it has 11% WACC. The project has a life of 4 years for capital budgeting purposes.

What is cash flow at time 0?