1. Blood donation from a new donor
2. Blood donation from an existing donor
3. Generate report on specific period for existing donors
4. Remove a unit of blood due to the expiration date
5. Report for the number of units of each group
5. Submit an Order
6. Update Order Status (Free OR Pending)
7. Report of Free Orders
8. Report of Pending Orders
9. Check how many times specific donor donated blood
10. The total monthly payment for blood for a certain period of time
11. The total blood units that are sold monthly
12. The highest day of blood selling for one year
13. The lowest day of blood selling for one year
14. Exit Function