Answer
(a) (2) To get back to the starting point, the student has to walk north of east.
(b) Displacement to get back to starting point is $111.8\,\mathrm{m}$.
Work Step by Step
(a) The student travels west and then, south. In order to retrace her steps, she has to go north and then, east. To take the direct route she has to go (2) north of east.
(b) To get back to the starting point, the student has to travel along the hypotenuse, as shown in the figure.
Displacement is given by -
$s=\sqrt{100^2+50^2}=111.8\,\mathrm{m}$.
