Represent the motion in the number line.
Movement to the east is movement to the negative side. Movement to the west is movement to the positive side.
Total displacement = -680m + 430m - 620m = -870m
Total displacement = 860m to the east.
Answer:

Explanation:
The speed is by definition the distance traveled divided over the time it takes to travel that distance. In this case, this distance is the circumference of the wheel, so we have:

where we have written the circumference in terms of its radius.
For our values we then obtain the value:

Answer: 0j
Explanation:
At that point potential energy is zero and kinetic energy is maximum.. P. E=mgh=0
Answer: The electric repulsion between the two protons is stronger than the gravitational attraction.
Explanation: Please see the attachments below
The answer is C but man if you have leak or a meltdown good luck to anyone downstream.