On January 2,2018 , David Corporation purchased a patent for $500,000. The remaining legal life is 12 years, but the company estimated that the patent will be useful only for eight years. In January 2020 , the company incurred legal fees of $45,000 in successfully defending a patent infringement suit. The successful defense did not change the company's estimate of useful life. How much amortization expense will David Corporation record on December 31 , 2020? A) 65,000 B) 80,000 C) 70,500 D) 70,000