Investment Useful life $1,000,000 12 years Estimated annual ne] cash inflows for first year $400,000 Estimated annual net cash inflows for second year $350,000 Estimated annual net cash inflows for next ten years. $300,000 Residual value $50,000 Depreciation method Required rate of return Straight-line 12% Calculate the payback period for the investment. 2.5 years 2.83 years 3.0 years 3.5 years