Answer:
Zero
Explanation:
Displacement is a vector connecting the initial position with the final position of motion of an object.
In this case, we have the following motion:
10 m north
30 m north
40 m south
If we take north as positive direction and south as negative direction, we can identify each motion using the following displacement vectors:
[tex]d_1 = +10 m\\d_2 = +30 m\\d_3 = -40 m[/tex]
So, the total displacement is:
[tex]d=d_1+d_2+d_3=10+30-40=0[/tex]
Which means that the final position of the motion corresponds to the initial position.
