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. 1 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.