An office administrator realizes that she is having trouble doing her work due to eyesight problems. Her optometrist determines that without glasses she can focus clearly only on objects that lie at distances between0.570mand5.30m.The optometrist decides that the best way to handle her eyesight problems is to prescribe bifocals that will give her normal visual acuity from25.0 cmout to infinity. After trying on several pairs of glasses frames, they agree that the glasses will be a distance of2.20 cmfrom her eyes.(a) Determine the refractive power needed for the bifocal part that will correct for her nearsightedness (include the sign). How is the virtual image (formed by her glasses) distance related to her unaided eye's far point and the distance between her glasses and eyes? What sign is associated with a virtual image?D