<span>-- the product of the net charges on the objects;. -- the distance between the centers of their net charges. (Pretty much identical to the formula for gravitational force)</span>
        
                    
             
        
        
        
Answer:
Waves with high frequencies have shorter wavelengths that work better  than low frequency waves for successful echolocation.
Explanation:
To understand why high-frequency waves work better  than low frequency waves for successful echolocation, first we have to understand the relation between frequency and wavelength.
The relation between frequency and wavelength is given by
λ = c/f
Where λ is wavelength, c is the speed of light and f is the frequency.
Since the speed of light is constant, the wavelength and frequency are inversely related.
So that means high frequency waves have shorter wavelengths, which is the very reason for the successful echolocation because waves having shorter wavelength are more likely to reach and hit the target and then reflect back to the dolphin to form an image of the object.
Thus, waves with high frequencies have shorter wavelengths that work better  than low frequency waves for successful echolocation.
 
        
             
        
        
        
I believe it she should use the first aid kit next
        
                    
             
        
        
        
Explanation:
The energy stored in coal is directly form the sun which is solar energy. This energy are preserved in carbon atoms and they originate from the life processes of a plant. 
- Plants carry out photosynthesis and produce their energy by this process. 
- Green plants have special adapted structures by which they trap solar energy from the sun and use it to produce their own food. 
- The food is used by plant for nutrition and life activities. 
- In essence the solar energy is converted to chemical energy in plants. 
- To form coal, when plants are rapidly buried their organic matter is preserved from decay by combination with oxygen. 
- More burial preserves the complex molecules that have stored during photosynthesis. 
- The carbon eventually aggregates for coal. 
learn more: 
Coal brainly.com/question/10055728
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