I believe that it is a chemical change.
        
                    
             
        
        
        
  The heat of fusion for water is the amount of energy needed for water to :
c.melt
        
             
        
        
        
Answer:
The great confrontation between the two men occurred  in 1686 when Newton published the first volume of his Principia and Hooke affirmed that it was he who had given him the notion that led him to the law of universal gravitation. Hooke demanded credit as the author of the idea but Newton denied it
Explanation:
 
        
             
        
        
        
Answer:
Ionosphere.
Explanation:
The atmospheric layer that is represented by F is known as IONOSPHERE. 
The characteristics of Ionosphere
1. It is considered to be located in the upper layer of the earth's atmosphere due to the location of region F.
2. It is ionized by solar radiation that contains an electrical charge. 
3. It functions as a reflector. This can be observed in radio waves broadcasting.
 
        
             
        
        
        
The answer is A. Most galaxies appear to be moving away from each other. Scientists discovered this when looking through very expensive microscopes, and saw that the universe was always growing and expanding, as if exploding from one point and moving outward.