public void Drive(double distance)
 {
     Tank.BurnFuel(distance / FuelEfficiency);
     KMs.Increment(distance);
 }
        //odometer odometer = new odometer();
        //fueltank fueltank = new fueltank();



        public void Drive()
        {
            Tank.BurnFuel(20 / FuelEfficiency);
            KMs.Increment(20);
        }