1. An object is at distance s from a thin glass lens of focal length f. The lens is surrounded by air. The image is at distance s' from the lens. Draw a graph of s' versus s. Explain physically why the graph varies as it does.

2. A thin lens has radii of curvature R1=-8.00 cm and R2=-6.00 cm, indices of refraction nred=1.50 and nviolet=1.53 for red and violet light, and is surrounded by air. An object at distance s=20.0 cm from the lens has an image at distance s' from the lens. Is there a second lens with nred, nviolet, and R2 as stated above, but a different R1 so that s' due to violet light and the second lens equals that due to red light and the first lens? Explain your result.