Rio Grande River sources: Rio Grande Natural Forest, San Juan Mountains, Canby Mountain
        
             
        
        
        
Answer:
They´re a source of invaluable information. The study of these cosmic materials allows us to gain knowledge about the history of the solar system, about processes and primary conditions in the universe. We can learn the age and the composition of the planetary building blocks, the temperatures reached at the surface and interiors of asteroids, what kind of effect do materials experience due to impacts in the past. 
Explanation:
 
        
                    
             
        
        
        
Answer:
d
Explanation:
desertification is the cutting down of trees the best way to fight the cutting down of trees is to plant more in order for them to grow