(Solved): Required information In her job as a dental hygienist, Kathryn uses a concove mirror to see the bac ...

Required information In her job as a dental hygienist, Kathryn uses a concove mirror to see the back of her patient's teeth. When the mirror is \( 1.10 \mathrm{~cm} \) from a tooth, the image is upright and \( 2.30 \) times as large as the tooth. What is the focal length of the mirror?