It helps relieve pressure and it calms down your brain so you can think clearly.
        
                    
             
        
        
        
The Mound Builders used metal tools, and were probably metal builders. Based on that information I would say the answer is B.Copper, because copper is a metal.
        
                    
             
        
        
        
Answer: Toothbrush Moustache
Explanation:Charlie Chaplin was one of the most famous wearers of the toothbrush moustache. In a 1933 interview, Chaplin said he added the moustache to his costume because it had a comical appearance and was small enough so as not to hide his expression. Adolf Hitler was a fan of Chaplin, but there is no evidence that Hitler modeled his mustache after Chaplain.
 
        
                    
             
        
        
        
It's harmony because of the complementary colors and the way the figures are proportioned in the piece. 
        
                    
             
        
        
        
The trombone does not belong to the wood wood section, the trombone is in the brass “family”.