Step 4.1 - Examine the following Customer-Order-Product-Depot ER-Diagram: street city state area_code number street city state zip area_code number first_name last_name depot_no depot address depot_phone (depot_name) customer address customer phone customer name Depot N Supplies Customer unit_cost customer_id Places Order area_code delivery phone number street Product Contains order delivery_address city state product quantity product no product name product price quantity order_total order_date order_no zip Step 4.2 - Design (write out) a relational schema for this E-R diagram. Underline the primary keys, show the foreign keys in italics, and draw arrows from the foreign keys to the primary keys