A point charge of -3.00 μC is located in the center of a spherical cavity of radius 6.90 cm inside an insulating spherical charged solid. The charge density in the solid is 7.35 × 10-4 C/m3. Calculate the magnitude of the electric field inside the solid at a distance of 9.30 cm from the center of the cavity.

A point charge of -3.00 μC is located in the center of a spherical cavity of radius 6.90 cm inside an insulating spherical charged solid. The charge density in the solid is 7.35 × 10-4 C/m3. Calculate the magnitude of the electric field inside the solid at a distance of 9.30 cm from the center of the cavity.