January 2021, Perez Corporation purchased a patent for a new consumer product for $620,000. At the time of urchase, the patent was valid for fifteen years. Due to the competitive nature of the product, however, the patent sestimated to have a useful life of only ten years. In 2026 the product was determined to be obsolete due to a petitor's new product. What amount of charge should Perez report on the income statement during 2026 related me patent, assuming straight-line amortization is recorded at the company's December 31 year-end? a. $640,000 b. $310,000 c. $42,000 d. $210,000