a person is to be fitted with bifocals. she can see clearly when the object is between 35.4 cm and 1.8 m from the eye. (a) Since the upper portion of the bifocals should be designed to enable her to see distant objects clearly, what is the power they should have? (Assume there is no significant distance between the eye and the glass lens.)
(b) The lower portion of the bifocals should enable her to see objects comfortably at 25.0 cm. What power should they have?