<em><u>Displacement is a vector quantity that describes the shortest distance or path from an initial position to the final position. </u></em>
Displacement combines both distance and direction of a motion along a straight line from the origin to the final position of a point.
In this case; we start with; 4 km north and 2 km south; to get 2 km North from the original position, adding 5 km north, we get 7 km north, the adding 5 km south we get a total displacement of 2 km north.
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