1. To calculate how many liters per vehicle fueled and convert it to price.
2. To calculate the sales of the fuel from beginning to ending of one shift.
3. To calculate sales inventory.
4. All the consumer purchase diesel and unleaded must be recorded and save for inventory use.
Get the type of purchase (ex. P.O or Cash Payment)
Get the kind of fuel to be purchase(diesel or unleaded)
Get how many liters to be fueled
Calculate fuel purchase and price per liter
Output the converted fuel liters into price
Calculate the content of the fuel reservoir from beginning to ending of one shift
Calculate liters sold
Output the total sales of one shift
5. Uses GUI window.