Tilly Company purchased a machine for $300,000. It is expected to have a useful life of 5 years and salvage value of 100,000 at that time. The date of purchase was Jan1, 2018 and the company uses the half year method. Requirements: 1. Calculate depreciation expense for 2018 and for 2019 using straight line depreciation. 2. Calculate depreciation expense for 2018 and 2019 using DDB