Address Full name and past medical history I think, sorry if I'm wrong
        
             
        
        
        
The answer is A) squeezing a stress ball to relax. 
        
             
        
        
        
Answer:
Hope you got it
Explanation:
Electromagnetic waves always travel at the same speed (299,792 km per second). This is one of their defining characteristics. In the electromagnetic spectrum there are many different types of waves with varying frequencies and wavelengths. They are all related by one important equation: Any electromagnetic wave's frequency multiplied by its wavelength equals the speed of light