Answer:
Compressions and Rarefactions
<em>A vibrating tuning fork is capable of creating such a longitudinal wave. As the tines of the fork vibrate back and forth, they push on neighboring air particles. The forward motion of a tine pushes air molecules horizontally to the right and the backward retraction of the tine creates a low-pressure area allowing the air particles to move back to the left.</em>
Explanation:
These regions are known as compressions and rarefactions respectively. The compressions are regions of high air presure while the rarefactions are regions of low air pressure.
<em>Sound waves can also be shown in a standard x vs y graph, as shown here. This allows us to visualise and work with waves from a mathematical point of view. The resulting curves are known as the "waveform" (i.e. the form of the wave.) The wave shown here represents a constant tone at a set frequency.</em>
 
        
             
        
        
        
Answer:
when one muscle is contracted, the other muscle from the pair is always elongated. for example, the biceps and tricep muscles work together to allow you to bend and straighten your elbow. when you want to bend your elbow, your bicep muscle contracts. and at the same time tricep muscles relaxes.
Explanation:
Hope this helped Mark BRAINLIEST!!
 
        
             
        
        
        
The Cell Wall protects the cell from particles outside.
        
             
        
        
        
Answer:
1. Use a Rain Barrel. There are several options when it comes to water catchment systems, so if you don't love the look of rain barrels, there are other systems.
2. Plant Trees or Shrubs. A great choice for any landscape, trees and shrubbery serve several purposes.
 
        
             
        
        
        
The negative impact humans could have on an ocean ecosystem is pollution, which can lead to a mass extinction on the wildlife.