Answer:
Journal entry.
Debit creditors account with $15,000 and credit company's sales account with $15,000
Being quarterly journal subscription paid in advance last year.
Explanation:
The advance subscription payments customers are taken as creditors of the company. The company owes them the service of mailing the quarterly journals to them. The total creditors payment ($45,000) will be recorded as credit entry in the books of the company's creditors account and as the company discharges the liability, the amount is passed to debit side of the creditor's account. We assume equal quarterly subscription amount, which will result in $15,000 for each quarter in a year.