A Simple Digital Camera Lens with Focal Length $f _ { O } = 3.00 \mathrm {~cm}$

A simple digital camera lens with focal length $f _ { O } = 3.00 \mathrm {~cm}$ perfectly focuses the image of an object on a CCD sensor located a distance $14.00 \mathrm {~cm}$ away from the lens. The object now moves away from the lens and the new distance between the lens and sensor is $13.00 \mathrm {~cm}$ .
(a) By what amount did the object change its distance from the lens?
(b) What is the new magnification?

A) (a) $0.08 \mathrm {~cm}$
(b) $3.33$
B) (a) $0.03 \mathrm {~cm}$
(b) $0.30$
C) (a) $12.22 \mathrm {~cm}$
(b) $4.33$
D) (a) $990.00 \mathrm {~cm}$
(b) $0.23$