A non conducting spherical shell, with an inner radius of 4.0 cm and an outer radius of 6.0 cm, has charge spread non-uniformly through its volume between its inner and outer surfaces. The volume charge density p is the charge per unit volume, with the unit coulomb per cubic meter. For this shell p = b/r, where r is the distance in meters from the center of the shell and b = 3.0μC/m2.What is the net charge in the shell?