A patent was acquired by Renfro Corporation on January 1, 2017, at a cost of $80,000. The useful life of the patent was estimated to be 10 years. At the beginning of 2020, Renfro spent $14,000 in successfully defending an infringement of the patent. At the beginning of 2021, Renfro purchased a patent for $21,000 that was expected to prolong the life of its original patent for 5 additional years.

Calculate the following amounts for Renfro Corporation.

(a) Amortization expense for 2017.

(b) The balance in the Patent account at the beginning of 2020, immediately after the infringement suit.

(c) Amortization expense for 2020.

(d) The balance in the Patent account at the beginning of 2021, after purchase of the additional patent.

(e) Amortization expense for 2021.

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