comparing three appreciation methods that's your industries purchase packaging and equipment on January $8$th for $$108,000$ the equipment was expected to have a useful life of $3$ years or $$21,600$ operating hours and a residual value of $$5,400$ equipment was used for $$8,640$ hours during year one $6,480$ hours in year $2$ and $6,480$ hours in year three.

Determine the amount of depreciation expense for the $3$ years ending december $31$st by $($a$)$ the straight line method $($b$)$ the units of activity method or $($c$)$ the double declining balance method also determinee the total depreciation expense for the $3$ years by each metho also determine the total depreciation expense for the $3$ years by each method.