One of Concord customers paid $17,000 to Concord in December 2020. This amount was included in Concord revenue for 2020. However, the product was not actually shipped to the customer until 2021. Assume a periodic inventory system is being used. (Credit account titles are automatically indented when the amount is entered. Do not indent manually. If no entry is required, select "No Entry" for the account titles and enter 0 for the amounts.)