fuel consumption small basic

GraphicsWindow.Title = "How expensive will your trip be?"
GraphicsWindow.Top = (Desktop.Height - GraphicsWindow.Height) / 2
GraphicsWindow.Left = (Desktop.Width - GraphicsWindow.Width) / 2
colour = GraphicsWindow.GetRandomColor()
colour2 = GraphicsWindow.GetRandomColor()
GraphicsWindow.BackgroundColor = colour
GraphicsWindow.BrushColor = colour2
GraphicsWindow.DrawText(0, 24, "Enter your total journey's distance in kilometers:")
Distance1 = Controls.AddTextBox(295, 20)
GraphicsWindow.DrawText(82, 46, "Enter your fuel consumption (KPL):")
Consumption1 = Controls.AddTextBox(295, 42)
GraphicsWindow.DrawText(103, 68, "Enter the price per liter for fuel:")
Price1 = Controls.AddTextBox(295, 64)
Controls.AddButton("Calculate", 190, 150)
Controls.ButtonClicked = Button
Sub Button
  GraphicsWindow.DrawText(0, 90, "It will cost you $")
  Distance = Controls.GetTextBoxText(Distance1)
  Consumption = Controls.GetTextBoxText(Consumption1)
  Price = Controls.GetTextBoxText(Price1)
  Total = Distance*Consumption*Price/100
  GraphicsWindow.DrawText(100, 90, Total)
EndSub