Answer
$100^\circ$, not an efficient walker.
Work Step by Step
Step 1. Using the given figure, we can identify the three sides as $5.2,3.6,3.2\ ft$
Step 2. The pace angle $\theta$ faces the longest side and using the Law of Cosines, we have
$5.2^2=3.6^2+3.2^2-2(3.6)(3.2)cos\theta$ and $cos\theta\approx-0.1667$
Thus
$\theta=acos(-0.1667)\approx100^\circ$
Step 3. The pace angle is not very large, indicating that this herbivore was not an efficient walker because it traveled too much sideways during each step.
