During 2016, Sheffield Corporation spent $165,600in research and development costs. As a result, a new product called the New Age Piano was patented. The patent was obtained on October 1, 2016, and had a legal life of 20 years and a useful life of 10 years. Legal costs of $41,040related to the patent were incurred as of October 1, 2016.

Prepare journal entries for the following.

1) On June 1, 2018, Sheffield spent $10,440to successfully prosecute a patent infringement suit. As a result, the estimate of useful life was extended to 12 years from June 1, 2018. Prepare journal entries required in 2018 and 2019.

2) In 2020, Sheffield determined that a competitor's product would make the New Age Piano obsolete and the patent worthless by December 31, 2021. Prepare journal entries required in 2020 and 2021.