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Shown below is the adjusted Trial Balance for Simon Inc., on December 31, after the first year of operations, after adjusting entries: Simon, Inc. Adjusted Trial Balance December 31 1,600 $ Cash Accounts Receivabl 4,000 Office Equipme 16,800 1,600 2400 Accumul ated Depreciat ion Capital Stock Retained Earnings Dividends Service 21,920 3,200 Service Fees Earned Wages Expense Supplies Expense Depreciat ion Expense 1,120 960 $ 28,640 $ 28,640 After closing the accounts, Retained Earnings at December 31 equals: Select one: e a. $19,360. o b. $18,400. c. Zero d. $16,640