Answer:
Income summary has a $208,630 credit balance before being closed
Explanation:
The closing entries should be:
Dr Service revenue 257,000
     Cr Income summary 257,000
Dr Income summary 48,370
     Cr Rent expense 10,700 
     Cr Utility expense 4,200 
     Cr Salary expense 19,200
     Cr Depreciation expense 9,700
     Cr Advertising expense 4,570
Income summary 
Debit               Credit
<u>18,370             257,000</u>
                        208,630
In order to close income summary:
Dr Income summary 208,630
     Cr Retained earnings 208,630
If you want to close dividends:
Dr Retained earnings 18,700
     Cr Dividends 18,700