He is incorrect because a catalyst is a substance that speeds up a chemical reaction so if there is no reaction to begin with a catalyst will not due anything.
        
             
        
        
        
Answer: Like us, fish also need to take in oxygen and expel carbon dioxide in order to survive. But instead of lungs, they use gills. ... As the fish opens its mouth, water runs over the gills, and blood in the capillaries picks up oxygen that's dissolved in the water.
 
        
             
        
        
        
Answer:
depended on applications of fertilizers, pesticides and irrigation to create conditions in which high-yielding modern varieties could thrive. 
Explanation: