Consider a mail order business in which employees take orders or parts from customers. Create a conceptual using the following information.

a. The mail order company has employees, each identified by a unique employee number, first and last name, and Zip Code.
b. Each customer of the company is identified by a unique customer number, first and last name, and Zip Code.
c. Each part sold by the company is identified by a unique part number, a part name, price and quantity in stock.
d. Each order placed by a customer is taken by an employee and is give a unique order number. Each order contains specified quantities of one or more parts. Each order has a date of receipt as well as an expected ship date. The actual ship date is also recorded.

Required:
Design an ER (Entity-Relationship) diagram for the mail order database and build the design using a data modeling tool such as ERwin or Rational Rose.