why is the income summary 52500?

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, $63,500; Dividends, $2,000; Sales, $56,000; Sales Returns and Allowances, $3,000; Sales Discounts, $1,500; Depreciation Expense, $25,000; and Salaries Expense, $23,000. All accounts have normal balances. Prepare the second closing entry by selecting the account names from the pull-down menus and entering dollar amounts in the debit and credit columns.