Mahmood Is Farsighted and Cannot See Objects Clearly That Are $+ 36.4 \mathrm {~cm}$

Multiple Choice

Mahmood is farsighted and cannot see objects clearly that are closer to his eye than 80.0 cm. What is the focal length of the contact lenses that will enable him to comfortably see objects at a distance
Of 25.0 cm from his eyes?

A) $+ 36.4 \mathrm {~cm}$
B) $+ 32.5 \mathrm {~cm}$
C) $+ 21.2 \mathrm {~cm}$
D) $- 21.2 \mathrm {~cm}$
E) $- 36.4 \mathrm {~cm}$