Final answer:
The term for the way the straw appears as if it's broken underneath the water's surface is refraction.
Step-by-step explanation:
The term for the way the straw appears as if it's broken underneath the water's surface is refraction. Refraction is the bending of light waves as they pass from one medium to another, such as from air to water. When Deena puts the glass aside, the light passing from the water to the air undergoes refraction, making the straw appear broken.
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