At December 31, cash per the bank statement was $15,200; cash per the company's records was $18,000. Two debit memoranda accompanied the bank statement: service charges for December of $23, and a $975 check drawn by Jane Jones marked NSF. Cash receipts of $10,000 on December 31 were not deposited until January 4. The following checks had been issued in December but were not included among the paid checks returned by the bank: no. 620 for $800, no. 630 for $2,800, and no. 641 for $4,598. a. Prepare a bank reconciliation at December 31. b. Prepare the necessary journal entry or entries to update the accounting records.