#### Answer

The radian measure of $\theta $ shown in the figure is $\theta =$ $\frac{s}{r}$.

#### Work Step by Step

If $s$ is the length of an arc in a circle and $r$ is the radius of the circle, then the angle $\theta $ that intercepts the arc is given by
$\theta =\frac{s}{r}\ \text{radians}$
Thus, the radian measure of $\theta $ shown in the figure is $\theta =$ $\frac{s}{r}$.