The following is a list of audit procedures that might be applied to sales transactions. Identify those procedures that would be applied using audit sampling

a. Scan the accounting records to identify large and unusual transactions.

b. Observe the mailing of monthly statements to customers.

c. Inspect sales invoices for indication of checking and recompute extensions and footings.

d. Trace shipping documents to sales invoices and compare details (customer, description, quantity, and amount). 

e. Foot sales journals and trace to the general ledger.