Given an effective tax rate $($ETR$)$ of $12\%,$ and average tax rate of $15\%$ and a marginal tax rate $($MTR$)$ of $27\%,$ what is the after$-$tax cost for a firm that purchased a $$100,000$ piece of equipment $3$ years ago that has a useful life $($for taxes$)$ of $9$ years and a residual value of $$10,000?$