While looking at her image in a cosmetic mirror, Dina notes that her face is highly magnified when she is close to the mirror, but as she backs away from the mirror, her image first becomes blurry, then disappears when she is about 28.0 cm from the mirror, and then inverts when she is beyond 28.0 cm. Based on these observations, answer the following questions about the mirror.
What is the focal length of the mirror?
What is the radius of curvature of the mirror?