For the multi-lens system in step 11, use the thin lens equation for each lens, the data you gathered, and the expected focal length of the converging lens to calculate the focal length of the diverging lens.

Data:

Expected focal length of diverging lens: -150mm

Distance between the crossed-arrow object and the 150mm lens (first lens): 40mm

Distance between the lenses: 60mm

Distance between the 75mm lens (second lens) and the location of the image: 420mm

Height of the image on the screen: 58mm

How am I supposed to set up and execute this problem?