Answer:
Im sorry but I will try my best for you!
Explanation: T.T''
 
        
             
        
        
        
Answer:
the concentrations of salt water because its being controlled by the scientists.
Explanation: the iv= between the control and expariment.
dv= data or out come
constant+ not changed at all
 
        
                    
             
        
        
        
populations were prevented from interbreeding by geographic isolation