Final answer:
On interstate highways, slower vehicles must travel in the right lane, except when passing.
Step-by-step explanation:
On interstate highways, slower vehicles must travel in the right lane, except when passing.
The right lane is designated for slower-moving traffic, allowing faster vehicles to safely pass on the left. This helps maintain a smooth flow of traffic and prevents congestion.
In certain situations, such as when there is heavy traffic or construction, slower vehicles may use other lanes for safety reasons, but the general rule is to keep right.