Answer:
Swift Company should charge depreciation expense of $55,556 to income statement for the year ended December 31, 2013.
Explanation:
Under straight-line method, depreciation expense is (cost - residual value) / No of years = ($500,000 - 0) / 6 years = $83,333 yearly depreciation expense.
Accumulated depreciation as at end of 20212 = $83,333 x 2 = $166,667
Net book value (NBV) becomes $500,000 - $166,667 = $333,333
New depreciation is ($333,333 - $0) / 6 years = $55,556 yearly depreciation expenses from 2013 onward.