Final answer:
If unable to move for an emergency vehicle on a multi-lane roadway, the correct procedure is to stop moving and remain stationary until the vehicle has passed. This ensures clear passage for the emergency responders and adheres to traffic laws.
Step-by-step explanation:
When you're on a multi-lane roadway and you cannot move for an emergency vehicle, the correct action is to stop moving and become stationary until it passes by. This is to ensure that you do not obstruct the path of the emergency vehicle, allowing it to reach its destination as quickly and safely as possible. If you hear the Doppler shift in an ambulance siren, for instance, it can indicate whether the ambulance is approaching or has passed, helping you decide when it's safe to proceed. In any case, safety and compliance with traffic laws should be your top priority in such situations.