A retail store wants to build an online system for their customer to place orders online and for pickup later from the store. Customers join the system by registering online (username (email), password, address, phone no) and including a credit card for use in online ordering; at that time they use login credentials (uername and password) to enter the online system. Customers who have joined the system can use the online system to search for products, select products, specify amounts or weights for products where necessary, and place orders for those products, specifying a pick-up time. (The system enforces a 24-hour minimum pick-up time). When an order has been placed, an email confirming its receipt and listing order details is sent to the customer. (Customers have the opportunity to edit their order for a certain period of time). When an order is received by the system it is forwarded to order processors, who collect and package up the ordered items, and sends an email confirming the completion of the order to the customer. The customer go to the store in the chosen pick-up time, call a number to inform his arrival, and waiting to the designated area. Cashier charges the customers' credit card appropriately and deliver the order. Customers can use the on-line system to check past orders, to inquire into order statuses, and take a short survey after every order. The system logs information on all orders, containing details on what was ordered, charges, and order status. One alternative scenario is worth noting. When customers order products, they are allowed to order only products or amounts of products that are currently present in inventory. When order processors are processing orders, however, inventory may have changed, and certain products (or requested amounts of those products) may no longer be available. Such products are omitted from the orders, or supplied to the extent possible. Such cases are noted and inform (by email and a phone call) to the customer. The customer is not charged for such items. Another alternative scenario is if customers do not show up in the chosen pick-up time, they will be charged based on their delay. 2. Prepare a system sequence diagram for (1) process an order