On January 2, 2021, Teal Mountain Company purchased a patent for $42,100. The patent has an estimated useful life of 25 years and a 20-year legal life. What entry would the company make at December 31, 2021 to record amortization expense on the patent? (Credit account titles are automatically indented when the amount is entered. Do not indent manually. List all debit entries before credit entries. If no entry is required, select "No Entry" for the account titles and enter O for the amounts.)