On October 1, the company received a $5,400 advance payment on services to be performed for one year. The services began immediately. The adjusting entry on December 31 needed for this event would include a: credit to Unearned Fees for $1,350 debit to Unearned Fees for $1,350 debit to Unearned Fees for $1,800 debit to Fees Earned for $5,400