Dorothy & George Company is planning to acquire a new machine at a total cost of $$52,400.$ The machine$$s estimated life is $6$ years and its estimated salvage value is $$500.$ The company estimates that annual cash savings from using this machine will be $$11,000.$ The company$$s after$-$tax cost of capital is $9\%$ and its income tax rate is $40\%.$ The company uses straight$-$line depreciation $($non$-$MACRS$-$based$).($Use Appendix C$,$ Table $1$ and Appendix C$,$ Table $2.)($Do not round intermediate calculations. Negative amounts should be indicated by a minus sign. Round "Payback period" to $2$ decimal places and all other answers to the nearest dollar amount.$)$

Required:

$1.$ What is this investment$$s net after$-$tax annual cash inflow?

$2.$ Assume that the net after$-$tax annual cash inflow of this investment is $$8,000$; what is the payback period in years?

$3.$ Assume that the net after$-$tax annual cash inflow of this investment is $$8,000$; what is the net present value $($NPV$)$ of this investment?

$4.$ What are the minimum net after$-$tax annual cost savings that make the proposed investment acceptable $($i$.$e$.,$ the dollar cost savings that would yield an NPV of $$0)?$