Because they Both work together to filter the water.  Also without them Precipitation wouldn't occur and there wouldn't be any water cycle. 
        
             
        
        
        
Answer:
Variability was seen as imperfection, so natural selection could only eliminate the inferior and imperfect, not giving rise to new things, new species.
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Answer:
its option A. bright tail feathers of peacocks during breeding season
Explanation:
 
        
             
        
        
        
Answer:
Commensalism
Explanation:
Commensalism is a relationship between species in which one benefits and the other is unaffected. Humans are host to a variety of commensal bacteria in their bodies that do not harm them but rely on them for survival
 
        
             
        
        
        
D, The cell take in water and food some of the food dissolve to create other things for the cells and they have structures that perform to help us survive.