On January 1, Hall \& Oates, CPAs received a $17,400 cash retainer for accounting services to be rendered ratably over the next 3 months. The full amount was credited to the liability account Unearned Service Revenue. Assuming that the revenue is recognized equally over the 3-month period, what adjusting journal entry should be made at January 31? \{List debit entry before credit entry. 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.)