Finch Sports Company is considering whether to purchase a new stamping machine that costs $4,000. The machine is efficient and should increase net income by $400 per year. Finch's engineers estimate the stamping machine to be good for 15 years. Required a. Determine the unadjusted rate of return based on the average cost of the investment. Note: Enter your answer as a whole percentage (e.g. .55 should be entered as 55 )