Please explain how to calculate, thanks.

EXERCISE 7-15 Internal Rate of Return and Net Present Value L07-2, L07-3 Henrie's Drapery Service is investigating the purchase of a new machine for cleaning and blocking drapes. The machine would cost $137,320, including freight and installation. Henrie's estimated the new machine would increase the company's cash inflows, net of expenses, by $40,000 per year. The machine would have a five-year useful life and no salvage value. Required: 1. What is the machine's internal rate of return to the nearest whole percent? 2. Using a discount rate of 14%, what is the machine's net present value? Interpret your results. 3. Suppose the new machine would increase the company's annual cash inflows, net of expenses, by only $37,150 per year. Under these conditions, what is the internal rate of return to the nearest whole percent