The answer would be (C) i believe. 
        
                    
             
        
        
        
The first step of cellular respiration is glycolysis, where a six carbon glucose is broken down into a three carbon, this is called pyruvic acid. You're welcome
If you want the other steps in cellular respiration or cytology, just ask, I'm an A+.
        
                    
             
        
        
        
Should be A the newer layers are usually on top
        
             
        
        
        
The correct answer is 3- <span>The smelt and alewife may out-compete the native fish by consuming all of the zooplankton.
The diagram tells us that zooplankton is eaten by smelts and alewifes. If these two species increase in number, less of the zooplankton will be left for plankton-eating fish, which is a native type of fish, to eat. 
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<span> smelt and alewife eat most of the existing plankton so, they are out-competing the native fish.</span>