' C ' is the only correct statement on the list.  We don't know anything about diagram-x or diagram-y because we can't see them.
 
        
                    
             
        
        
        
Answer:
The height of building should be 98.13 m plus the height of Daniel. Since the 63° was measured from his eye level.
Explanation:
 
        
             
        
        
        
Did you try looking it up ?
        
             
        
        
        
Erosion, weathering, mechanical changes, chemical changes. 
Really, any interaction can change the composition of a rock whether it be done by man or through nature.