A driver is transporting a placardable quantity of Division 1.1 explosives. Under hazardous materials regulations, which of the following is a specific rule for parking the vehicle?

1. The driver may leave the vehicle unattended for up to 45 minutes for a meal break.
2. The vehicle must be parked on the shoulder of the highway if a rest stop is unavailable.
3. The vehicle must be attended at all times unless parked in a designated safe haven.
4. The vehicle must not be parked within 5 feet of the traveled portion of a road.