Which one are you trying to answer ?
Answer: Nearsightedness, Farsightedness and Astigmatism. Nearsightedness (myopia) is a very common condition in which the light coming into the eye is not focused properly onto the retina, making it difficult to see objects far away. The condition is usually caused by an elongation of the eyeball that occurs over time.
Explanation:
Ex: Draw the United States, then draw a transform plate boundary starting in the middle of California down into the ocean.
When light travels from air into water, it slows down, causing it to change direction slightly. This change of direction is called refraction. When light enters a more dense substance (higher refractive index), it 'bends' more towards the normal line
