A physics class is investigating the magnification produced by a converging lens. An illuminated object of height $h_0=3.0cm$ is set up. The distance $u$ between the illuminated object and the lens is varied, and for each distance, the screen is adjusted until a sharp image of height $h_I$ is formed. Measurements are recorded in Table 3.1. Table 3.1: | $u/cm$ | $h_I/cm$ | $S=\frac{h_0}{h_I}$ | | :---: | :---: | :---: | | $40.0$ | $3.0$ | | | $45.0$ | $2.4$ | | | $50.0$ | $2.0$ | | | $55.0$ | $1.7$ | | | $60.0$ | $1.5$ | | | $65.0$ | $1.3$ | | | $70.0$ | $1.2$ | |