A jogger starts from the south-west corner A of a rectangular park ABCD whose length AB is 120m and breadth BC is 80m. He runs once along the boundary in the order A→B→C→D→A and then immediately runs from A to the mid-point M of side AB.
(i) Calculate the total distance covered by the jogger up to the point M.
(ii) Calculate the magnitude of the net displacement of the jogger from his starting point A to point M.
(iii) Which of the two quantities, distance or displacement, changed when the jogger ran from A back to A, and why? State your answer with reason.