Answer:
The answer is below
Step-by-step explanation:
The clock in the CPU is made of three elements including the following:
1. Crystal oscillator
2. A counter
3. A holding register
All these clock elements combined and generate interrupts at known periods or duration.
However, the clock has a powered battery back up which is implemented with a form of low-power circuitry similar to that of digital watches.
The purpose is to prohibit the current time from being failed when the computer is powered off or shut down.