Howard Co. manufactures household goods and maintains its accounting system using a re-

lational database. In order to prepare information about purchase transactions, the company uses the following tables in its database. The fields that appear in each table are in brackets following the table.

- vendors [vendor ID, name, address, phone number]

- purchase orders [purchase order number, vendor ID, order date, product ID, order quantity]

- materials [product ID, product name, quantity on hand, unit cost]

- purchase invoice [purchase invoice number, purchase order number, invoice date]

- cash payments [purchase invoice number, cash payments amount, payment date]

A purchase order is prepared when materials are ordered from a vendor. A purchase invoice is recorded from billing information supplied by the vendor.

For each of the following events, identify the tables that would be needed to record the event.

1. Placed an order with Jones Co. for materials on November 3.

2. Received the materials from Jones Co. on November 16.

3. Received a bill from Jones Co. for the purchase order on November 28.

4. Sent a check to Jones Co. for the purchase on December 5 .