Nash Company purchased machinery on January 1,2020 , for $81,600. The machinery is estimated to have a salvage value of $8,160 after a useful life of 8 years. Compute 2020 depreciation expense using the straight-line method. Depreciation expense $ Compute 2020 depreciation expense using the straight-line method assuming the machinery was purchased on September 1 , 2020. Depreciation expense $