Answer:
Nitrogen cycle
Explanation:
Nitrogen fixation is the process by which atmospheric nitrogen is converted by either a natural or an industrial means to a form of nitrogen such as ammonia. In nature, most nitrogen is harvested from the atmosphere by microorganisms to form ammonia, nitrites, and nitrates that can be used by plants.
 
        
             
        
        
        
Answer:
A. three pounds
Explanation:
it definitely doesn't weigh ounces :)
 
        
                    
             
        
        
        
Answer:
When water falls and seeps into the ground it actually interacts with the lithosphere 
 
        
             
        
        
        
Answer: A. Environmental drivers plus genetic variation in the population result in natural selection
Explanation: over geological time environmental conditions change. Organisms do not survive in one environmental niche with traits adapted to a possible future change that might suit those traits. Adaptation is not a matter of choice: adapt if possible or go extinct.
There is a (badly named) concept called pre-adaptation, which is that variations in some existing trait render adaptation to a different environment more likely.