An investment project has annual cash inflows of $$3,600,$$$4,500,$$$5,700,$ and $$4,900,$ for the next four years, respectively. The discount rate is $15$ percent.

a$.$ What is the discounted payback period for these cash flows if the initial cost is $$6,300?($Do not round intermediate calculations and round your answer to $2$ decimal places, e$.$g$.,32\mathrm{.}16.)$

b$.$ What is the discounted payback period for these cash flows if the initial cost is $$8,400?($Do not round intermediate calculations and round your answer to $2$ decimal places, e$.$g$.,32\mathrm{.}16.)$

c$.$ What is the discounted payback period for these cash flows if the initial cost is $$11,400?($Do not round intermediate calculations and round your answer to $2$ decimal places, e$.$g$.,32\mathrm{.}16.)$

$\backslash$table$[[$a$.$ Discounted payback period,,years$],[$b$.$ Discounted payback period,,years$],[$c$.$ Discounted payback period,,years$]]$