Activity 5: Lens Equation Directions. Solve the following lens problems. Show your solution. 1. A coin with a diameter of 3.10 cm is placed 25.0 cm from a concave lens with a focal length of -11.0 cm. What are the distance and the size of the image? 2. An object is placed at 80.0 cm from a convex lens of focal length 25.0 cm. Find the distance between its image and lens. 3. Determine the image distance and image height for a 6.00 cm tall object placed 48.0 cm from a convex lens having a focal length of 15.0 cm