To conduct tests of controls of a client's internal control procedures, auditors design a test of controls audit program. This audit program is a list of procedures to be performed, and each procedure is directly related to one or more important client control procedures. Auditors perform the audit procedures to obtain evidence about the operating effectiveness of the client's control procedures. The controls listed below relate to a system for processing sales transactions. Each numbered item indicates an error or other misstatement that could occur and a specified control procedure that could prevent or detect it. 1. The company wants to avoid selling goods on credit to bad credit risks. Poor credit control could create problems with estimating the allowance for bad debts and a potential error by overstating the realizable value of accounts receivable. Therefore, the control procedure is as follows: Each customer order is to be reviewed and approved for 30-day credit by the credit department supervisor. The supervisor then notes the decision on the customer order, which eventually is attached to copy two of the sales invoice and filed by date in the accounts receivable department. The company used sales invoices numbered 20,001 to 30,000 during the period under review. 2. The company considers sales transactions complete when shipment is made. The control procedures are as follows: Shipping department personnel prepare pre-numbered shipping documents in triplicate, sending one copy to the customer and filing the other copy in numerical order in the shipping department file. The shipping clerk marks up copy three of the invoice, indicating the quantity shipped, the date, and the shipping document number, and sends it to the billing department where it is taken as authorization to complete the sales recording. Copy three is then filed in a daily batch in the billing department file. These procedures are designed to prevent the recording of sales for which no shipment is made or before the date of shipment. 3. The company wants to control unit pricing and mathematical errors that could result in overcharging or undercharging customers, which would cause overstatement or understatement of sales revenue and accounts receivable. The accounting procedures are as follows: Billing clerks use a catalogue list price to price the shipment on invoice copies one, two, and three. They compute the dollar amount of the invoices. Copy one is sent to the customer. Copy two is used to record the sale and later is filed in the accounts receivable department by date. Copy three is filed in the billing department by date. 4. The company needs to distinguish sales to subsidiaries from other sales, so that the consolidated financial statement eliminations will be accurate. That is, the company wants to avoid the error of understating the elimination