10-6. (Payback period, NPV, PI, and IRR calculations) You are considering a proj- ect with an initial cash outlay of $80,000 and expected free cash flows of $20,000 at the end of each year for 6 years. The required rate of return for this project is 10 percent. a. What is the project's payback period? b. What is the project's NPV? c. What is the project's PI? d. What is the project's IRR?