I think A is the youngest layer, because of the new sediments that fell upon the animal.
        
                    
             
        
        
        
Answer:
phosphorus
Explanation:
Since Phosphorus is an essential component of phospholipids, nucleic acids, phosphoproteins (casein), high energy phosphate esters (ATP), hexose phosphates, creatine phosphate, it also provides strength to the exoskeletons of clams and oysters.
 
        
             
        
        
        
The observation that deals more with senses instead of graphs and data. 
 
        
             
        
        
        
Answer:
individuals of the same species that live in the same area
 
        
             
        
        
        
Answer:
<h3>A</h3><h3>Tree roots anchor soil in place,preventing runoff. </h3>
Explanation:
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