Mechanics Question

I don't understand how to work out part b

the velocity becomes zero twice in the interval 0 to 2 seconds.

let us call these two times P and Q

from 0 to P the velocity is positive, so the displacement increases.

from P to Q the velocity is negative, so the displacement decreases

from Q to 2 the velocity is positive again, so the displacement increases.

you need to work with the distances, not the displacements... in all 3 cases above the distance traveled is increasing.

I think I understand? How would I find the distance? Integrate the velocity function in parts? Pythagorus?