In order to perform an evacuation, which of the following must there be enough time for?

The ability to warn people is crucial during an evacuation. Ensuring that the affected individuals are aware of the need to evacuate allows them to take appropriate and timely action to move to safety. Warning people in advance helps minimize panic and confusion, enabling an orderly evacuation process. It provides necessary information and instructions on where to go and what to do, which is essential for maintaining safety and order during an emergency situation.

In contrast, the other options, while they may be relevant in certain contexts, do not directly contribute to the immediate and critical need for an evacuation. Rescheduling public events, completing the business workday, or rerouting public transportation may be logistical considerations but are secondary to the primary concern of ensuring that everyone is informed and able to evacuate safely in a timely manner.