As a new auditor of a large accounting firm, you have been assigned to review internal controls over mail cash receipts of McMahon Company. Your review reveals that checks are promptly endorsed "For Deposit Only", but no list of the checks is prepared by the person opening the mail. The mail is opened either by the cashier or by the employee who maintains the accounts receivable records. Mail receipts are deposited in the bank weekly by the cashier. Instructions: Write a letter to Bob McMahon, owner of McMahon Company, explaining the weaknesses in internal control and your recommendations for improving the system