Answer:
The velocity of the Mr. miles is 17.14 m/s.
Explanation:
It is given that,
Mr. Miles zips down a water-slide starting at 15 m vertical distance up the scaffolding, h = 15 m
We need to find the velocity of the Mr. Miles at the bottom of the slide. It is a case of conservation of energy which states that the total energy of the system remains conserved. Let v is the velocity of the Mr. miles. So,

g is the acceleration due to gravity

v = 17.14 m/s
So, the velocity of the Mr. miles is 17.14 m/s. Hence, this is the required solution.
Answer: Force = 81 N
Explanation:
from Columbs law,
F = k(q1*q2)/r²
k = 9 x 10^9 Nm²/C²
F = (9 x 10^9)x (0.9x10^-5 x 2.5x10^-4)/(0.5)²
F = 81 Newtons