Problem 3 South Plains Corp. purchased a machine on March 26, 2012 for $500,000. The machine was estimated to have a useful life of 12 years and a salvage value of $50,000. South Plains originally used the straight-line depreciation method, taking one-half-year of depreciation in the year of purchase. In 2015 South Plains switched to the sum-of-the-years-digits depreciation method for 2015 and all future years. What is depreciation expense for 2015