Final answer:
The fire alarm system must have a secondary power supply that provides power within a certain time period of failure of the primary power supply.
Step-by-step explanation:
The subject of this question is Engineering as it pertains to fire alarm systems. Fire alarm systems are designed and implemented by engineers to ensure safety in buildings. Engineers are responsible for designing and specifying the various components and requirements of the system.
The grade level for this question is College, as it is discussing a specific requirement for fire alarm systems that requires an understanding of engineering principles and technical specifications.
In accordance with fire safety standards, the secondary power supply of a fire alarm system should provide power within a certain time period in case the primary power supply fails. The specific time period may vary depending on local regulations and building codes, but it is typically within 10 seconds of failure.