The answer is $13,572

Could someone explain how this is the answer?

I got it wrong and just want guidance on how to get this answer.

TB MC Qu. 3-159 (Algo) The following account balances... The following account balances are taken from the December 31, 2020, financial statements of ABZ Advertising Company. The company uses accrual basis accounting. The following activities occurred in 2021: 1. Performed advertising services on account, $64,050. 2. Received cash payments on account, $12,300. 3. Received deposits from customers for advertising services to be performed in 2022,$3,800. 4. Made payments to suppliers on account, $5,320. 5. Incurred $52,400 of operating expenses; $45,400 was paid in cash and $7,000 was on account and unpaid as of the end of the year. What is the balance in the Cash account at December 31, 2021