<span>C. Travel toward the beach faster</span>
The correct answer for the question is Chordophone
Chordophone is an instrument in which a stretched, vibrating string produces the initial sound. Strings instruments produce sound through the vibration of strings. The length, tightedness, and thickness determines the sound produced by the strings.
Answer:

Explanation:
We have the following data:
- distance covered by the child: d = 2 m (length of the slide)
- time taken to cover this distance: t = 3 s
- initial velocity of the child: 0 m/s (he starts from rest)
So we can find the acceleration by using the equation:

Where a is the acceleration.
Substituting the values and solving for a,

Heat engines are less than 100% efficient because absolute zero cannot be reached
Answer A is incorrect
A crest is just one point. It is not the distance between 2 crests.
B is incorrect
A trough is just 1 point. It is not the distance between 2 troughs.
C is incorrect.
the amplitude measures the height of a crest from the middle of the wave to the crest (or trough).
D is the correct answer. That is the distance between 2 crests or 2 troughs