A manufacturer is considering two alternative machine replacements. Machine 1 costs $1 million with an expected life of 5-years and will generate after-tax cash flows of $350,000 a year. At the end of 5 years, the salvage value on Machine 1 is zero, but the company will be able to purchase another Machine 1 for a cost of $1.2 million. The replacement Machine 1 will generate after-tax cash flows of $375,000 a year for another 5 years. At that time its salvage value will also be zero. The manufacturer's second option is to buy Machine 2 at a cost of $1.5 million today. Machine 2 will produce after-tax cash flows of $400,000 a year for 10 years, and after 10 years it will have an after-tax salvage value of $100,000. The cost of capital for both machines is 12 percent. What is the NPV for both machine 1 and for machine 2?

How do you calculate the NPV if we don't have a discount rate?