Would it be the Stereomicroscope?
        
             
        
        
        
Correct me if i'm wrong i think the best answer would be d. the cow uses all of the corn's energy for life processes.
        
             
        
        
        
~Hello There!~
It would be C. Digestive. 
Hope This Helps You!
Good Luck :)
Have A Great Day ^_^
- Hannah ❤
 
        
                    
             
        
        
        
The velocity (speed) of a sound wave (any wave in fact) is related to its frequency and wavelength by the equation . This is easy to remember since it's a distance divided by a time because frequency is the inverse of the period.
Since for sound traveling through the given solid object we have that  and , the speed of sound will be:       
this is what i looked up and got
 
        
             
        
        
        
<span>A substance that is made of atoms of more than one type bound together is called a <span><u>compound</u>.
</span>A compound is a</span><span> substance consisting of atoms or ions of two or more different elements in definite proportions joined by chemical bonds into a molecule. </span><span>
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