On July 1, 2015, ABC Corporation purchased a patent asset for $21,600 and a trademark asset for $12,400. The patent's economic useful life is 16 years from the purchase date. The trademark has an indefinite life. How much amortization expense should ABC recognize for these intangible assets in calendar year 2015? O a $1,350 b. $1,062.50 c. $675 d. $2,125