A delivery robot moves along a city grid where each street is straight and meets others at right angles. Starting from the warehouse at point W, the robot follows these instructions:
1. Travel 120 m north to point X.
2. Travel 90 m east to point Y.
3. Travel 40 m south to point Z.
4. Travel 150 m west to point M.
5. Travel 70 m north to the final drop-off point N.
(i) Draw a neat, scaled diagram of the robot’s route, labelling all points.
(ii) Calculate the total distance travelled by the robot.
(iii) Determine the magnitude of the net displacement from W to N.
(iv) If the robot had instead returned directly from N to W along the shortest possible straight path, how much additional distance did it actually travel compared with this direct return?