Buffalo Company purchased a computer system for $74,050 on January 1, 2016. It was depreciated based on a 7-year life and an $17,700 salvage value. On January 1, 2018, Buffalo revised these estimates to a total useful life of 4 years and a salvage value of $10,000. Buffalo uses straight-line depreciation. Prepare Buffalos entry to record 2018 depreciation expense