Answer:
The atmosphere is the blanket of gases which surrounds Earth. It is held near the surface of the planet by Earth's gravitational attraction.
Explanation:
 
        
                    
             
        
        
        
A Trombe wall (Trombe rhymes with prom, by the way) is a wall that warms trapped air, and then circulates it to help heat a house. Trombe walls are ideally made out of a material with a fairly high thermal mass materials (like bricks or concrete), and are often painted black to improve heat conduction
 
        
             
        
        
        
I may be wrong but I think it’s the second one. They speed up reactions, and there’s a certain enzyme for a certain reaction.