Question 1 The Blood Bank Testing Unit is a unit within the College Street, Red Cross Blood Donor Centre. On the day following a blood donation, the Blood Bank unit tests all blood for blood type and potential viral agents. They send the results of these tests to the Processing Ofce (another unit of the Centre). For each tested blood unit, they fill out a form which lists the blood unit number, the blood type, the date and the results of the test. If the tests indicate that the blood may be contaminated with a viral agent, the blood unit is destroyed. This is indicated on the test form. Blood units have a limited shelf life. The Blood Bank receives a list every day of those units which have exceeded their shelf life. These are discarded and the list sent back to the Processing Ofce with a signed indication of the disposal of the units. The Blood Bank also distributes blood to various hospitals requesting blood. Requests usually come in for specic blood types. The Blood Bank prepares refrigerated containers of these units and distributes them to the hospital vans when they arrive to pick up their supply. The Blood Bank receives a listing for each hospital and the specific units of blood supply to the hospital from the Processing Ofce. The order is printed in triplicate. 1When the order is lled, the lab technician signs the order and returns a copy to the Processing Office. A copy of it travels with the blood to the requesting hospital. The final copy is kept in the Blood Bank records, but discarded after one year. Draw a level 0 and level 1 Data Flow Diagram (DFD) for the Blood Bank Testing Unit System. [30 marks]