The unadjusted trial balance of Anniston Air Purification System at December 31, 2018, and the data needed for the adjustments follow. ANNISTON AIR PURIFICATION SYSTEM Unadjusted Trial Balance December 31, 2018 Balance Account Title Debit Credit Cash 57,600 Accounts Receivable 19,700 Prepaid Rent 2,900 Office Supplies 1,800 Equipment 22,000 Accumulated Depreciation Equipment $ 3,900 Accounts Payable 2,900 Salaries Payable Unearned Revenue 3,100 Common Stock 43,800 Dividends 9,900 Service Revenue 15,300 Salaries Expense 3,300 Rent Expense Depreciation Expense-Equipment Advertising Expense 1,800 Supplies Expense $ 69,000 Total 5 69.000 Adjustment data at December 31 follow: a. On December 15, Anniston contracted to perform services for a client receiving $3,100 in advance. Anniston recorded this receipt of cash as Unearned Revenue. As of December 31, Anniston has completed $2,100 of the services. b. Anniston prepaid two months of rent on December 1. (Assume the Prepaid Rent balance as shown on the unadjusted trial balance represents the.wo months of rent prepaid on December 1.) c. Anniston used $750 of office supplies. d. Depreciation for the equipment is $850. e. Anniston received a bill for December's online advertising, $1,100. Anniston will not pay the bill until January (Use Accounts Payable.) f. Anniston pays its employees on Monday for the previous weeks wages. Its employees earn $3,500 for a five day workweek. December 31 falls on Wednesday this year, g. On October 1, Anniston agreed to provide a four-month air system check (beginning October 1) for a customer for $3,400. Anniston has completed the system check every month, but payment has not yet been received and no entries have been made