The following accounts are taken from the December 31, 2010, financial statements of A to Z Advertising Company Advertising revenue Cash Accounts receivable Interest expense Accounts payable Operating expenses Unearned revenue Equipment Income tax expense 46,882 1,556 7,336 2,319 5,040 37,660 1,218 18,448 2,366 The following activities occurred In 2011: 1. Billed customers for advertising services rendered, $55,400 2. Recelved cash from customers In pament of their accounts, $10,600. 3. Incurred $45,200 of operating expenses of which $39,200 was pald in cash and $6,000 was on account and unpald as of the end of the year. 4. Pald suppliers $5,400 on the accounts payable. 5. Recelved deposits from customers of $2,540 for advertising services to be performed in 2012