Answer:
Step-by-step explanation:

B. The equation has one real root.
Answer:
-(1/4πϵ0)Qq/r^2
Step-by-step explanation:
Firstly we have to assume the uniform shell of radius R as point charge as the point charge.
Then apply coulomb equation of electrostatic charge (Fe=q1q2/4πϵ0r2) where the q1 and q2 are point charges and r is the distance from the centre of charges.
But remember there's a condition that r>>R otherwise the charge will get non-uniformely distributed.
How to find the area of a circle:
The area of a circle can be found by multiplying pi ( π = 3.14) by the square of the radius
If a circle has a radius of 4, its area is 3.14*4*4=50.24
If you know the diameter, the radius is 1/2 as large.
Answer:
Get the mean and standard deviation with excel spreadsheet and do the calculation as shown in details below.