Lens-Maker's Formula: in the Figure, the Radius of Curvature of the Curved

Multiple Choice

Lens-maker's formula: In the figure, the radius of curvature of the curved part of the lens is 24.0 cm, and the refractive index of the lens material is 1.750. What is the focal length of the lens?

A) +32.0 cm
B) -32.0 cm
C) -16.0 cm
D) +13.8 cm
E) -13.8 cm