Depreciation Methods A machine costing $180,000 was purchased May 1. The machine should be obsolete after four years and, therefore, no longer useful to the company. The estimated salvage value is $15,000. Calculate the depreciation expense for each year of its expected useful life using each of the following depreciation methods: (a) straight-line, (b) double- declining balance. For double-declining balance, do not round until your final answer. Round your final answers to the nearest dollar. a. Straight-line: Year 1: $ Year 2: Year 3: Year 4: Year 5: b. Double-declining balance: Year 1: $ Year 2: Year 3: Year 4: Check