Final answer:
In a high-rise fire, the second chief is most likely to assume the role of Incident Commander, taking overall charge of the scene and coordinating the emergency response.
Step-by-step explanation:
In the event of a high-rise fire, the second chief will most likely assume the role of Incident Commander. The Incident Commander is responsible for the overall management of the scene and coordination of emergency response efforts including fire suppression, search and rescue, and potential evacuation. Other roles such as Safety Officer, Evacuation Coordinator, and Water Supply Chief are typically separate positions that might be filled by different members of the response team. The Evacuation Coordinator works closely with other emergency personnel to ensure the safe and orderly evacuation of occupants.