On 1/1/14 Jameson Co. purchased equipment at a cost of $420,000. The equipment was estimated to have a useful life of five years and a salvage value of $60,000. Jameson uses the sum-of-the-years-digits method of depreciation. What should the accumulated depreciation be at 12/31/17. (a) $240,000 (b) $288,000 (c) $336,000 (d) $360,000