a machine costing $212600$ with a $4-$year life and an estimated $19000$ salvage value is installed in luther company's factory on january $1.$ the factory manager estimates the machine will produce $484000$ units of product during its life. It actually produces the following units: $121,600$ in year $1$; $122900$ in year $2$; $120900$ in year $3$; $128600$ in year $4.$ the total number of units produced by the end of year $4$ exceeds the estimate$-$ this difference was not predicted. note: the machine cannot be depreciated below its estimated salvage value. compute depreciation for each year $($and total depreciation of all years combined$)$ for the machine under straight$-$line method, units$-$of$-$production method, and double$-$declining$-$balance method