Answer:
D) the bending of a wave as it moves around an obstacle or passes through a narrow opening 
Explanation:
Even though light travels in straight line, it will bend around objects if their size is comparative to its wavelength. This phenomenon is called diffraction.
Light will also bend if the light travels from one medium to another medium at an angle, but that is called refraction.
Diffraction occurs in one medium. Refraction occurs when light travels from one medium to another.
 
        
             
        
        
        
If you were to sit a hot cup of water out side it would frezze faster
        
             
        
        
        
Answer:
The refractive index of glass, 
Solution:
Brewster angle is the special case of incident angle that causes the reflected and refracted rays to be perpendicular to each other or that angle of incident which causes the complete polarization of the reflected ray.
To determine the refractive index of glass:
 (1)
                 (1)
where
 = refractive index of glass
 = refractive index of glass
 = refractive index of glass
 = refractive index of glass
Now, using eqn (1)



 
        
             
        
        
        
I am not so sure about this it is too difficult