Can I see the book you read for I can answer and it more info because your question doesn’t make sense
In telecommunication systems, Carrier frequency is a technical term used to indicate: ... The frequency of the unmodulated electromagnetic wave at the output of a conventional amplitude-modulated (AM-unsupressed carrier), or frequency-modulated (FM), or phase-modulated (PM) radio transmitter.
Answer:

Explanation:
Given
See attachment for the graph
Required
Determine the frequency
Frequency (F) is calculated as:

Where
T = Time to complete a period
From the attachment, the wave complete a cycle or period in 3 seconds..
So:


--- Approximated
If I drop my egg unprotected, then it will break.