Answer:
AM radio, FM radio, microwaves, sodium light. 
Explanation:
Electromagnetic radiation are waves from electromagnetic field which spread through the space or any other material medium and carries radiating energy. Examples includes X rays, radio waves, Gamma rays, etc. Exposure to high level of electromagnetic radiation could be harmful to human body, on the other hand, science as not been able to prove that exposing humans to low level electromagnetic radiation is harmful to our health. 
 
        
             
        
        
        
Answer:it should be Newton’s second law 
Explanation: lmk if I’m wrong 
 
        
                    
             
        
        
        
Answer: 
 "The distance between crests is 3 cm." 
Explanation:
If he writes down "The distance between crests is 3 cm." 
That means he is describing the wavelength of a wave and not longitudinal wave. He ought to write something about " direction "
Longitudinal waves are waves in which the displacement of the medium is in the same direction as, or parallel to, the direction of propagation of the wave. While 
Wavelength is the distance between the two successfully Crest or trough 
 
        
             
        
        
        
Answer:
75 m
Explanation:
The horizontal motion of the projectile is a uniform motion with constant speed, since there are no forces acting along the horizontal direction (if we neglect air resistance), so the horizontal acceleration is zero.
The horizontal component of the velocity of the projectile is

and it is constant during the motion;
the total time of flight is
t = 5 s
Therefore, we can apply the formula of the uniform motion to find the horizontal displacement of the projectile:
