Draw an activity diagram for processing an order, which involves several tasks as fol- lows.

Once an order is received, the customer is sent an invoice, as well as associates work on the refill order. Once the order is ready, if a rush order is requested, the order is sent by overnight delivery, otherwise, it is sent by regular delivery. Customer receives invoice and eventually makes a pay- ment. So, once the payment is received, processing for order is considered complete, and order will be closed.