of $$23,780$ at the end of each year for six years. The discount rate for this project is $9\mathrm{.}7$ percent.

a$.$ What are the project's payback and discounted payback periods?

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

c$.$ What is the project's PI$?$

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

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