Well mostly because it's for oceans and lakes that have waves. so if you don't live near any of these, you wouldn't be getting power. <span />
Answer:
The frequency is
Explanation:
From the question we are told that
The frequency of the tuning fork is 
The beat period is 
Generally the beat frequency is mathematically represented as


The beat frequency is also represented mathematically as

Where
is the frequency of the piano
So
Definitely ball and basket