A car is travelling at 120 km/h (75 mph). When applied the braking system can stop the car with a deceleration rate of 9.0 m/s2. The typical reaction time for an alert driver is 0.50 s versus 2.0 s for a sleepy driver. Assuming a typical car length of 5.0 m, calculate the number of additional car lengths it takes the sleepy driver to stop compared to the alert driver.