Question

what is the image distance and image size if a 10.00 cm.tall light bulb placed a distance of 91 cm. from a convex lens having a focal length of 30.8 cm?

Answer 1

$$\dfrac 1f=\dfrac 1o+\dfrac 1i,\\\space\\ i=46.6\text{ cm}.\\\space\\ h_i=\dfrac ioh_o=14.1\text{ cm}.$$