Activation energy is the minimum quantity of energy that the reacting species must possess in order to undergo a specified reaction. 
 for example , striking a match on the side of a matchbox provides the activation energy, in the form of heat produced by friction.
        
                    
             
        
        
        
Answer:
Rough endoplasmic reticulum differ from smooth endoplasmic reticulum by the presence and absence of ribosomes in their surface.
Explanation:
Rough endoplasmic is named so because RER contain ribosomes at their surface and due to the presence of ribosomes rough endoplasmic reticulum play an importnt role in protein synthesis or translation.
  Whereas smooth endoplasmic reticulum does not contain any ribosome in its surface.smooth endoplasmic reticulum helps in the biosynthesis of lipid and steroids along with detoxification of toxic compounds.
 
        
             
        
        
        
<span>The reaction required an input of energy.</span>
        
                    
             
        
        
        
It is in standard notation
in scientific notation it would be  is 5.4 x 10^6