A spherical charge distribution has a volume charge density that is a function only of r, the distance from the center of the distribution (i.e. ρ = ρ(r)). If ρ(r) is given below, determine the electric field as a function of r using Gauss's Law.
(a) ρ = A/r with A constant for 0 ≤ r ≤ R
(b) ρ = ρ0 (i.e. constant) for 0 ≤ r ≤ R.