30. Colton Company purchased a patent on January 1, year 1, for $178,500. The patent was amortized over its remaining legal life of 15 years expiring on January 1, year 16. During year 4, Colton determined that the economic benefits of the patent would not last longer than 10 years from the date of acquisition. What amount should be charged to patent amortization expense for the year ended December 31, year 4?

A. $10,500

B. $20,400

C. $35,700

D. $17,800

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