Velocity is height , speed is an object being propelled by force
        
                    
             
        
        
        
The study of EM is essential to understanding the properties of light, its propagation through tissue, scattering and absorption effects, and changes in the state of polarization. ... Since light travels much faster than sound, detection of the reflected EM radiation is performed with interferometry.
        
             
        
        
        
I really don’t know but I think it’s D 
 
        
             
        
        
        
Around 27 satelites is used for GPS technology
        
                    
             
        
        
        
Answer:

Explanation:
Initial potential energy of the given spacecraft is given as

so we have

so we have






now total work done to move it to infinite is given
W = 0 - U
