Answer:
18.1 km
Explanation:
The problem can be solved by resolving the vector representing the displacement into its components along the north-south and east-west directions.
Look at the figure below: the displacement is the vector that connects A (starting point) to B (ending point), while the distance covered during the return trip is the sum of the length of the two components along the north-south and east-west direction.
Using vector rules, we find the magnitude of the two components:
East-west:
[tex]d_x = 13 cos 35^{\circ}=10.6 km[/tex]
North-south:
[tex]d_y = 13 sin 35^{\circ}=7.5 km[/tex]
So the total distance covered during the return trip is
[tex]d=d_x + d_y = 10.6 + 7.5 = 18.1 km[/tex]
