Final answer:
Local laws dictate the specific speed at which drivers must slow down when approaching a stopped emergency vehicle on roads with speed limits of 80km/h or more. The options provided in the question do not specify this required speed, emphasizing the need to refer to local traffic regulations for the correct procedure.
Step-by-step explanation:
When approaching a stopped emergency vehicle with speed limits of 80km/h or higher, the required action is not specified among the options provided (a. Stop moving and become stationary till it passes by, b. Run toward the ambulance, or c. Run alongside the ambulance). Generally, in many jurisdictions, you are required to slow down and move over if possible to give space to the emergency vehicle. The exact speed to which you must reduce your speed may vary by location and is typically stipulated in the highway traffic acts or road safety laws of the area. It's essential to check the local traffic regulations for the correct procedures and speed reductions required when approaching stopped emergency vehicles. Always prioritize safety and follow the laws designed to protect emergency personnel on the roads.