Optics of the Eye: A person's near point is 25 cm, and her eye lens is 2.7 cm away from the retina. What must be the focal length of this lens for an object at the near point of the eye to focus on the retina?
A. -3.4 cm
B. -2.4 cm
C. 2.4 cm
D. 3.4 cm
E. 2.6 cm
Answer: C
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