There is only one main element involved in the fusion reactions inside the sun; Hydrogen, but if you need a second element then it is more than likely that the question is asking for the isotope of hydrogen that is called <span>deuterium.
So basically, Hydrogen and Deuterium; an isotope of hydrogen</span>
        
             
        
        
        
Hot packs or a med used for reducing swelling
        
             
        
        
        
Answer:
Enzymes speed up a chemical reaction making the reaction easier to occur. 
 
        
             
        
        
        
Option - IT IS BASED ON PREDICTION 
because they have not had any way of telling where or when it has happened or occurred so you must predict how it happens or works.
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Multicellular 
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