How much gasoline remains in the KIA Rio III tank when the light is lit

The KIA Rio III fuel tank is designed for forty-three litres. The fuel indicator lamp is lit when the tank remains, on average, about seven litres. There is a small error of temperature of air or road gradient. Thus, we can go to the remaining petrol tank in the tank 100 km along the road. The amount of fuel in urban areas depends on traffic congestion (average 50 km).