At December 31, 2019, Pina Co. reported the following information on its balance sheet.

Accounts receivable		$962,200
Less: Allowance for doubtful accounts		78,000

During 2020, the company had the following transactions related to receivables.

1.		Sales on account		$3,670,800
2.		Sales returns and allowances		48,500
3.		Collections of accounts receivable		2,819,100
4.		Write-offs of accounts receivable deemed uncollectible		90,000

5.

Recovery of bad debts previously written off as uncollectible

28,400

Please explain how you got the answer.