Gulf Consulting Co. purchased equipment in 2017 for $600.000. In a disclosure note, Gulf indicates that it uses straight-line depreciation over five years and uses the half-year convention. Salvage value is estimated as $60,000 What is the book value of Gull's equipment on December 31, 2020? A. $378,000 B. $222.000 C. $168,000 D. Some other amount