1.) Consider the human eye to be composed of a thin lens of uniform index of refraction n = 1.43, with fluid of n = 1 inside, with the light-receptive cells a distance 24.6mm from the lens. The eye can "focus" on different distances by changing the radius of curvature of its lens
2.) find the radius of curvature for this lens when you are looking at an object a distance of 61.5 mm from your eye's lens. (all incident light rays must still hit the light-receptive cells at the same distance as before)