On one of the shelves in your physics lab is displayed an antique telescope. a sign underneath the instrument says that the telescope has a magnification of 23.0 and consists of two converging lenses, the objective and the eyepiece, fixed at either end of a tube 81.0cm long. assuming that this telescope would allow an observer to view a lunar crater in focus with a completely relaxed eye, what is the focal length fe of the eyepiece? note that to view the crater with a completely relaxed eye, the eyepiece must form its image at infinity and that images formed by telescopes of this nature are always inverted. fe = ? cm