Answer: Mississippi River has always influenced productivity in the Gulf.
Explanation:
 
        
                    
             
        
        
        
Answer:
Viscosity of magma depends mainly on composition, temperature, and gas ... 
 The arrival on the surface of magma that has lost its gas ..... It is a 0-to-8 index of increasing explosivity. 
 
        
                    
             
        
        
        
Contour lines on a map display the differences in elevation. Hope this helps