Jackson Corporation acquired equipment on January 1, 2010, for $320,000. The
equipment had an estimated useful life of 10 years and an estimated salvage
value of $25,000. On January 1, 2013, Jackson Corporation revised the total
useful life of the equipment to 6 years and the estimated salvage value to be
$20,000. Using the straight-line method of depreciation, what is the book value
as of December 31, 2013?