An inventory Control System (ICS) at its most basic tracks items for sales and notifies you when your stock is running low. Assume this is a retailer and not manufacturing firm so inventory increases when items are received from a supplier and decreases when items are sold to a customer. Inventory quantities are decrease based on data exchanged with the sales control system (SCS) and increased based on data exchanged with the Purchase Control System(PCS). The SCS processes sales orders received from customers while the PCS processes purchase orders sent to suppliers. Assume that paying suppliers and invoicing customers are outside the scope of the ICS. The ICS uses a single data store named INVENTORY. If inventory-on-hand falls below a minimum quantity, the ICS will generate a purchase order request which is sent to PCS. The PCS then creates and transmits a purchase order to the supplier. When the items are physically received, the PCS transmit the list of received items to the ICS. The SCS receives a sales order from the customer and transmit the inventory quantity to be decreased to the ICS when an order has been approved for fulfillment. Draw the context diagram and level 1 DFD