Pressure at a given surface is given as ratio of normal force and area
so here force due to heel of the shoes is given as 80 N
and the area of the heel is given as 16 cm^2
so we can say

here we have
F = 80 N



so pressure at the surface due to its heel will be 5 * 10^4 N/m^2
he basket ball diameter used by NBA men players is around 9.55 inches
So diameter = 9.55 inch = 0.243 m
So radius of basket ball = 0.1215 m
Volume , 

So volume of basket ball used by men NBA players = 7.5 L
Answer:
The magnitude of each force is 2.45 x 10⁻¹⁶ N
Explanation:
The charge of proton, +q = 1.603 x 10⁻¹⁹ C
The charge of electron, -q = 1.603 x 10⁻¹⁹ C
Distance between the two charges, r = 971 nm = 971 x 10⁻⁹ m
Apply Coulomb's law;

where;
k is Coulomb's constant = 8.99 x 10⁹ Nm²/C²
q₁ and q₂ are the charges of proton and electron respectively
F is the magnitude of force between them
Substitute in the given values and solve for F

Therefore, the magnitude of each force is 2.45 x 10⁻¹⁶ N