$($Payback period, NPV$,$ PI$,$ and IRR calculations$)$ You are considering a project with an initial cash outlay of $$70,000$ and expected free cash flows of $$26,000$ at the end of each year for $6$ years. The required rate of return for this project is $8$ percent.

a$.$ What is the project's payback period?

b$.$ What is the project's NPV$?$

c$.$ What is the project's $\frac{?}{PI}?$

d$.$ What is the project's IRR?

a$.$ The project's payback period is years. $($Round to two decimal places.$)$