Final answer:
When a motorist is passed by another vehicle, they should stay in the proper lane, slow down, and return to their original lane after the pass is complete.
Step-by-step explanation:
When a motorist is passed by another vehicle, it is important for the motorist to stay in the proper lane and slow down to make the pass easier for the other motorist. After the passing vehicle is well ahead, the motorist should return to their original lane.
In the given scenario, Peter is stuck behind a slow driver and wants to pass. Once he has passed the car, he should return to his original lane.