Explanation:
Much energy is demanded within a short period in a sprint as opposed to long-distance that mainly demands stamina. During sprints, therefore, the energy demands by the muscles my outpace the supply by energy because oxygen is not reaching fast enough for aerobic cellular respiration. This is why sprinting cannot be sustained for long without accumulation of lactic acid in muscles – due to glycolysis metabolisms being the main source of energy.
IN long substance however, the runner does not sprint the entire marathon but run at sustainable speeds allowing the energy demands by the muscles to be met by the more effective aerobic respiration 
 
        
             
        
        
        
The stage at which the development of the brain reaches its adult is the middle childhood. A child's Brain undergoes a period of development from birth to three-producing more than a million neural connections each second. This development is influenced by many factors, which include the child's relationships, experiences and environment.
        
             
        
        
        
<span>The answer is a), all red, as no white alleles are present in the parents, [ and hence cannot be passed on to the offspring. Showing work- Let R represent the dominant (red) allele: RR(male) x RR(female) ----> All RR offspring.</span>
        
                    
             
        
        
        
Because bacteria mutates that's why we have a new flu vaccine every year , because strains of DNA in the bacteria change all the time.