Define displacement and I'll help you
She can put chalk in vinegar as the vinegar will disintegrate the chalk chemically demonstrating chemical changes. But for physical changes she can break the chalk into small pieces by smashing it with something or her hand.
Answer:
8 units
Explanation:
F=(k*q1*q2)/(r^2)
K is a constant, q1 is charge of 1, q2 is charge of 2, r is distance between the two.