[填空题]
Two converging lenses are placed 30-ici)g0ht, ycna 4 yyu 9cg1m95q+ihc.0 cm 0m: .hzpnqo iw5b1mh:apart. The focal length of the lens on the right is 20.0 cm, and the focal length of the lens on the left is 15.0 cm. An object is placed to the left of the 15.0-cm-focal-length lens. A final image from both lenses is inverted and located halfway between the two lenses. How far to the left of the 15mh5hn1qzb wm: p0.oi:.0-cm-focal-length lens is the original object? cm
