I don't know your options but it's probably an insulator.
<u>Answer:</u>
<em>When red light enters the lens its wavelength decreases but its frequency remains the same.
</em>
<u>Explanation:</u>
Lens is made of glass which is a <em>denser medium</em> when compared with air. Thus light will undergo refraction and bend toward the normal. On entering a denser medium from rarer medium the speed of light decreases.
<em>Speed, frequency and wavelength of an electromagnetic wave</em> are related according to the equation.
<em> v=ϑλ
</em>
Where is <em>v is the frequency, λ is the wavelength and v is the speed of the em wave.
</em>
On entering the lens the wavelength of the red light as well as speed decreases but the<em> frequency remains the same.
</em>
The speed and velocity of a moving body become identical when it tends to move in a straight line.
Blood is essential for good health because the body depends on a steady supply of fuel and oxygen to reach its billions of cells. Even the heart couldn't survive without blood flowing through the vessels that bring nourishment to its muscular walls.
Answer:
The near point is 
Explanation:
From the question we are told that
The power is 
The distance from the eye is 
The distance of the book from the eye is 
Generally the focal length of the glasses is
=> 
=> 
=> 
The object distance is evaluated as
=> 
=> 
The image distance is evaluated from lens formula as
=> 
=> 
=> 
The near point is evaluated as
=> 
=>
