Can someone please help by drawing a Data Flow Diagram DFD for this scenario.

ALL THE HELP THAT I CAN GET WILL BE APPRECIATED!

The Restaurant Buying Cooperative (RBC) is a group of independent restaurants in the tri-state area who have banded together to combine their buying power for non-perishable foods (e.g. flour, spices, tea and coffee.) Each week each restaurant owner prepares and submits their orders to RBC. RBC buys in bulk quantities to get discounts. Thus they may buy more of an item than is ordered in a particular week and keep the remainder in inventory in their warehouse for future orders. The orders from each restaurant are received and added to the Weekly Orders list. On Wednesdays RBC compares the Weekly Orders to the Warehouse Inventory file to determine what items and quantities need to be purchased. Purchase orders are generated and sent to the appropriate suppliers. Copies of these orders are placed in the Purchase Orders file. When shipments from the suppliers arrive, the RBC employees check what was actually received, compare what was received to what was ordered in the Purchase Orders file, and update the warehouse inventory file.

The Externals that are being used are: Resturant, Supplier