Two identical charged balls interact with force F. 1) How will the force of their interaction change

Two identical charged balls interact with force F. 1) How will the force of their interaction change if the distance between them is increased by 5 times? 2) How will the force of their interaction change if the charge of the balls is increased by 4 times?

F = kqq / R ^ 2
A) given:
F
q (1) = q (2)
R (1) = R
R (2) = 5R
F (1) = kqq / R ^ 2
F (2) = kqq / 25R ^ 2
F (1) / F (2) = kqq / R ^ 2: kqq / 25R ^ 2
F (1) / F (2) = kqq / R ^ 2 * 25R ^ 2 / kqq
F (1) / F (2) = 25
25F (2) = F (1)
Answer: will decrease 25 times
B) given:
F
q (1) = 4q (2)
R (1) = R (2)
F (1) / F (2) = kqq / R ^ 2: k4q4q / R ^ 2
F (1) / F (2) = kqq / R ^ 2 * R ^ 2 / k4q4q
F (1) / F (2) = 1/16
16F (1) = F (2)
Answer; will increase 16 times