Final answer:
When an emergency vehicle with flashing lights is approaching, even on the opposite lane of a two-way road, you must stop your vehicle to allow safe passage.
Step-by-step explanation:
If an emergency vehicle is coming toward you with its lights flashing, you must stop your vehicle, even if it's in the opposite lane of a two-way roadway. This action is necessary to ensure that the emergency vehicle can pass safely and quickly, as well as to comply with traffic laws.
Ignoring this requirement could lead to dangerous situations and is also against the law. A good practice is to always be aware of the sounds and sights around you, such as Doppler shift in an ambulance siren, which can help you determine when an emergency vehicle is approaching.