Yup, I think you add all of them
Explanation : Explain each characteristic of sound waves.
Intensity : the intensity of the sound wave is understand as the power carry by sound wave per unit area in the direction perpendicular to that area.
Loudness : loudness is the quality of the loud and soft of the sound wave.
Frequency : Human normal hear sound frequency between 20 Hz to kHz.
Pitch : Pitch is the quality of low and high of sound wave . pitch relates to the frequency of the slowest vibration in the sound wave for simple sound.
<h3><u>Answer;</u></h3>
Electron cloud
<h3><u>Explanation;</u></h3>
- <em><u>An atom is the smallest particle of an element that can take part in a chemical reaction. Atom is made up of two parts ; that is the nucleus and the electron cloud. The nucleus contain subatomic particles; protons and neutrons, while the electron cloud contains the electrons.</u></em>
- <em><u>The electron cloud is the largest part of the atom and is mostly an empty space. Most of an atom is a cloud of electrons surrounding a space called the nucleus with tiny protons and neutrons.</u></em>
Answer:
80%
Explanation:

800 / 1000 = 0.8
Efficiency = 0.8 *100 = 80%
Answer: friction reduces the speed during motion
Explanation:
The more the friction, the lesser the speed during motion