Answer:
There are 887.5 number of excess electrons on the each spheres.
Explanation:
It is given that, the force of repulsion between two spheres is, 
We know that the force of attraction or repulsion between charges is given by :

It is assumed that the separation between the spheres is 20 cm or 0.2 m. So,


Let there are n excess electrons that must be present on each sphere. It can be given by using quantization of charge as :



n = 887.5 electrons
So, there are 887.5 number of excess electrons on the each spheres. Hence, this is the required solution.
Protons
electrons are negatively charged
neutrons are neutral
Pressure and heat. I hope this helps
Answer:
it's B I think I did this the other day tbh sorry if it's wrong btw hope this helps