Final answer:
Refraction of light causes the lines to look bent when viewed through the glass of water.
Step-by-step explanation:
When light passes from one medium (air) to another medium (water), it changes direction, a phenomenon known as refraction. This change in direction is due to the change in the speed of light as it enters the new medium. The bending of light causes the lines to look bent when viewed through the glass of water.
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