Answer:
5.en
6.ex
7.ex
8.en
Explanation:
<h3>#CARRY ON LEARNING</h3><h3>#BRAINLITS </h3>
1.) Pitch
2.)Wavelength
3.)Density/Elastic Properties-b. Two of the above
4.)Liquids
5.) I'm not sure but I'm pretty sure it's the Doppler effect
6.) Frequency Increases
Ernest Rutherford is the answer you are looking for my friend.
Meters per second squared:

If you think about it, acceleration is about how fast speed changes. Speed is measured in meters per second:

So if you take that and just measure it over time, you get meters per second squared.