Your firm has estimated the following cash flows for a capital investment project. The firm's required rate of return is 10%. What is the project's payback period? Cash Flow -$185,000 at time o 55,000 at year 1 55,000 at year 2 55,000 at year 3 45,000 at year 4 45,000 at year 5 45,000 at year 6 3.0 years 2.5 years 3.5 years 4.5 years 4.0 years