If the power of a lens is - 4.0 D, then it means that the lens is a

power 4dFor the perfect blend, pour one packet of 4D Mix Pack powder into 16-24 ounces of cold water, shake well until fully dissolved, and enjoy. This ensures youPower of the lens (P) = 4 D. Refractive Index (r) = 1.5. To Find: The radius of curvature. Calculations: The following equation determines a lens's power: where P is the power of