Final answer:
Certain vehicles are required by law to stop at all railroad crossings, except in certain exemptions.
Step-by-step explanation:
The vehicles that must stop at all railroad crossings, except when specifically exempted by law, are:
- All school buses.
- All vehicles carrying passengers for hire.
- All commercial vehicles transporting more than 8 people.
- All commercial vehicles with a gross vehicle weight rating of more than 26,000 pounds.
Other vehicles such as private passenger vehicles and motorcycles may be exempt from stopping at certain crossings if there are signs indicating that they do not need to stop.