A sound wave is a wave of compression and rarefaction, by which sound is propagated in an elastic medium such as air.
Answer:

Explanation:
Given that,
The length of a string, l = 0.87 m
Speed of the ball, v = 3.36 m/s
We need to find the acceleration of the ball. The acceleration acting on the ball is centripetal acceleration. It is given by :

So, the acceleration of the ball is
.
<span>So we want to know what kind of wave is the scientist is studying while studying earthquakes. Waves that produce earthquakes are mechanical waves. Gamma rays and radiowaves are both electromagnetic waves and don't require a medium but mechanical do. So the correct answer is mechanical waves.</span>