because each sales center process many purchase orders, we consider SALES_CENTER as the parent entity and PURCHASE_ORDER as the child entity. click connector tool on the tool bar. move the mouse cursor over the parent entity SALES_CENTER. when a red rectangle appears, click the parent entity. then hold the mouse and move the cursor over to the child entity PURCHASE_ORDER. click the child entity when a red rectangle appears. a nonidentifying relationship connector is automatically draw from the parent entity to the child entity