These are selected 2022 transactions for Grouper Corporation: Jan. 1 Mar. 1 Purchased a copyright for $142,800. The copyright has a useful life of 7 years and a remaining legal life of 33 years. Purchased a patent with an estimated useful life of 6 years and a legal life of 21 years for $88,200. Sept. 1 Purchased a small company and recorded goodwill of $152,200. Its useful life is indefinite. Indicate the amount of amortization expense on December 31, 2022, for Grouper Corporation. Amortization expense $ 20400