Final answer:
The runner's distance is 4 km and his displacement is 0 km each morning.
Step-by-step explanation:
The runner's distance can be calculated by adding the distance he runs from his home to the park and the distance he runs back home. In this case, the runner runs 2 km north to the park and then 2 km south back to his home. So the total distance he runs each morning is 2 km + 2 km = 4 km.
Displacement, on the other hand, is the straight-line distance between the initial and final positions of the runner. Since the runner starts and ends at his home, his displacement is 0 km.