Graphic representing a concave curve based on fuel consumption in litres per 100km over speed in kilometres per hour. A “sweet spot” is demarcated between 50 and 80 kilometres an hour where fuel consumption is the lowest on the concave curve (7 litres per 100 kilometres)

Image illustrates 2 vehicles travelling on a road 25 kilometres in length. The front vehicle is travelling at 120 kilometres per hour. The rear vehicle travels at 100 kilometres per hour. The front vehicle travels the 25 kilometres, 2 minutes faster than the rear vehicle but needs more money to pay for fuel.