A 12-meter coach is negotiating a highway exit roundabout with a radius of 25 meters. If the driver increases speed from 20 km/h (5.56 m/s) to 40 km/h (11.11 m/s), how does the lateral acceleration (ay = v²/R) acting on seated and standing passengers change?

1. Lateral acceleration remains identical because vehicle mass is unchanged
2. Lateral acceleration doubles from 1.24 m/s² to 2.48 m/s²
3. Lateral acceleration quadruples from 1.24 m/s² to 4.94 m/s², drastically increasing rollover and passenger fall risk
4. Lateral acceleration drops to zero due to electronic stability control (ESP) intervention