Elements Inc. sells electrical components to department stores and also has cash sales to electricians. All sales have invoices. Cash sales are recorded to the cash receipts journal and cash is deposited to the bank daily. All sales to stores are credit sales and are handled by sales clerks by telephone. Sales clerks take customer's requests, check the authorized customer list for credit limits, prepare sales invoices, and send copies to the inventory control department, who send ordered goods to the shipping department. For cash sales, inventory clerks bring items sold to the sales counter and goods are given to the purchaser at the time of sale. For credit sales, shipping clerks sign the inventory control copy of sales invoices and then prepare shipping invoices. A copy of sales invoices are forwarded to accounting so that clerks can enter sales into the sales journal. Required: Design two audit procedures providing evidence over the occurrence of sales, and two audit procedures for completeness of sales.