College Physics 10th Edition by Raymond Serway,Chris Vuille

Exercise 33

An object 10.0 cm tall is placed at the zero mark of a meterstick. A spherical mirror located at some point on the meterstick creates an image of the object that is upright, 4.00 cm tall, and located at the 42.0-cm mark of the meterstick. (a) Is the mirror convex or concave (b) Where is the mirror (c) What is the mirror's focal length