Answer:
Karen must recognize income of $20,000 in 2019 and $500 in 2020
Step-by-step explanation:
Accrual basis of accounting states that income must be recognized in the period when it is earned and expenses must also be recognized when it is incurred.
Therefore, since the goods was sold in December 2019 and $500 interest was paid with the principal in April 2020, Karen must recognize income of $20,000 in 2019 and $500 in 2020.