Select 20 customer balances and confirm the amounts owed with the customers. Select a sample of 20 duplicate sales invoices. Examine the attached sales order for the signature of the credit manager to authorize credit 1. Substantive Test of Transactions 2. Substantive Test of Balances 3. Analytical Procedures Calculate expected commission expense by multiplying sales by the commission rate. Compare this expected amount with the recorded balance, and follow up appropriately. 4. Substantive Test of Disclosures 5. Test of Controls Select 20 sales recorded in the sales journal. Vouch each of these transactions to a copy of the sales invoice, customer order and bill of lading noting quantities and amounts