0 mark is your answer because you want to start at 0
Answer:
The Answer is A They can damage hearing.
Explanation:
I took the Test
The frequency of the wave is 6800 Hz
<u>Explanation:</u>
Given:
Wave number, n = 20
Speed of light, v = 340 m/s
Frequency, f = ?
we know:
wave number = 
Therefore, the frequency of the wave is 6800 Hz
5.
explanation: the answer is 5
Folds and faults are difficult to identify because they occur in the interior of rocks and also due to the dense nature of the materials.
<h3>What are faults and folds?</h3>
Faults are lines of weakness are present in materials dues to uneven positioning of the particles of the material.
Folds occurs when infolds occur in materials.
Faults and folds usually occur in rocks.
Folds and faults are difficult to identify because they occur internally and also due to the dense nature of the materials.
Learn more about faults and folds at: brainly.com/question/14240712
