Identify the Data Flow Diagram elements (data flow, data source/destination, processes, data store) in the following narratives:

- Retail stores requisition: A retail store electronically submits a retail store requisition to the central warehouse when it needs inventory or supplies. The warehouse shipping clerk fills the orders from inventory and authorizes store deliveries.

- Purchase requisition: The system notifies the inventory control clerk when the quantity on hand for an item stored in the central warehouse falls below the designated reorder point and prepares a purchase requisition. The inventory control clerk adjusts the purchase requisition as needed, approves it, and forwards it to the purchasing department.