An optical system is located in air. Let OO' be its optical axis, F and F' are the front and rear focal points, H and H' are the front and rear principal planes, P and P' are the conjugate points. By means of plotting find:
(a) The positions F' and H' (Fig. 5.11a);
(b) The position of the point S' conjugate to the point S (Fig. 5.11b);
(c) The positions F, F', and H' (Fig. 5.11c, where the path of the ray of light is shown before and after passing through the system).

(0- *p' p' (6) (a) (c)