Answer: (C) A hot spot 
Explanation:
  A hot spot is created in the volcanic peaks and it is basically developed over the plume. The mantle plumes are the areas of the up-welling and the hot mantle areas. Magma created by the problem area ascends through the unbending plates in the lithosphere layer. 
 It produces the dynamic volcano at the surface of the earth. In the mantle area, the hot spot are generated in which the rocks are get melted for generating the magma. The hot spot generated the heat are basically comes from the middle of the earth. 
  
 
        
                    
             
        
        
        
Answer:
 The longest time period is eons. 
 
        
                    
             
        
        
        
Answer:
<h3>The correct answer is A.</h3>
Explanation:
<h3>Becuase there was always a large labor force for the agricultural industry so this has not been a major development over the past 50 years.</h3>
 
        
             
        
        
        
Answer:
because there might be changes in the future which could make the estimates unreliable for example war or decline in economy
Explanation: