PLEASE EXPLAIN WHY THIS IS RIGHT

The company's adjusted trial balance includes the following accounts balances: Cash, $15,000; Equipment, $85,000; Accumulated Depreciation, $25,000; Accounts Payable, $10,000; Retained earnings, $59,000; Dividends, $2,000; Fees Earned, $56,000; Depreciation Expense, $25,000; and Salaries Expense, $23,000. All accounts have normal balances. Prepare the third closing entry by selecting the account names from the pull-down menus and entering dollar amounts in the debit and credit columns. Answer is complete and correct. No Date General Journal Debit Credit 1 Dec. 31 8,000 Income summary Retained earnings 8,000