These are selected 2017 transactions for Riverbed Corporation: Jan. 1 Purchased a copyright for $134,250. The copyright has a useful life of 5 years and a remaining legal life of 31 years. Mar. 1 Purchased a patent with an estimated useful life of 5 years and a legal life of 24 years for $63,900. Sept. Purchased a small company and recorded goodwill of $154,900. Its useful life is indefinite. Prepare all adjusting entries at December 31 to record amortization required by the events. (Credit account titles are automatically indented when the amount is entered. Do not indent manually. If no entry is required, select "No Entry" for the account titles and enter o for the amounts.) Date Account Titles and Explanation Debit Credit Dec. 31 Amortization Expense 26850 68 (To record amortization of Copyrights) Dec. 31 Amortization Expense (To record amortization of Patents) Dec. 31 Amortization Expense 10650 Patents (To record amortization of Goodwill)