Answer:
The distance is 35.0 m
Step-by-step explanation:
- Distance corresponds to the amount of space travelled by an object, regardless of the direction of the motion. Therefore, if an object moves several times into different directions, the distance can be simply calculated by adding the distance covered during each motion.
In this case, the ball moves a first time by
and a second time by
, so the total distance is

- Displacement corresponds instead to the spatial difference between the starting point and the final point of the motion: since the ball here travelled 30.0 m south and 5.0 m north, we must take into account the opposite directions in the two motions, by adding a negative sign. So, the displacement of the ball is
(in the south direction)