Bates Company purchased equipment on January 1, 2006, at a total invoice cost of $600,000. The equipment has an estimated salvage value of $15,000 and an estimated useful life of 5 years. What is the amount of accumulated depreciation at December 31, 2007, if the straight-line method of depreciation is used?a. $120,000b. $240,000c. $117,000d. $234,000