Physics 2: Optics

You want to form an image on a screen 10 m from a mirror. If the image is 7 times bigger than the object, what type of mirror do you need? What is the radius of curvature?

An object is placed at a distance of 30 cm from a concave lens of focal length 15 cm, h$_I$ = 2 cm. Determine the position of the image, the linear magnification, and h$_0$.

An object is 20 cm in front of a lens of focal length 9.5 cm. A second lens of focal length -30 cm is 15 cm behind the first lens. Find the location of the final image and its magnification.