Carla Vista Bus Lines uses the units$-$of$-$activity method in depreciating its buses. One bus was purchased on January $1,2025,$ at a cost of $$150,000.$ Over its $4-$year useful life, the bus is expected to be driven $245,000$ miles. Salvage value is expected to be $$7,900.($a$)$Compute the depreciation cost per unit. $($Round answer to $3$ decimal places, e$.$g$.6\mathrm{.}251.)$Depreciation cost per unit