Answer:
Debit to Air Traffic Liability , $500.
Explanation:
Air Traffic Liability is an important key term for airline officials and even investors to know. It involves money the airline has collected, but service that has yet to be provided.
We had two flights December 27, 2018, and the return flight to Baltimore is on January 10, 2019. But, the customer paid on December 1, 2018. This imples that we need to adjust the entry on December 31 for $500, because the service will be fully provided in 2019.