3) You are considering the purchase of one of two machines required in your proa process. Machine A has a life of two years. Machine A costs $50 initially and then S per year in maintenance. Machine B has an initial cost of $90. It requires $40 in maintenance for each year of its three-year life. Either machine must be replaced at end of its life. Which is the better machine for the firm? The discount rate is 15 per and the tax rate is zero