1. A hollow metal sphere has an inner radius of 7.0 cm and an outer radius of 10.0 em and is centered on the origin. The surface charge density on the inside surface is -300 nC/m and is uniform while the surface charge density on the outer surface is +300 nC/m' and is also uniform. (Possibly useful information: the surface area of a sphere is 4 * ) a. Is there a point charge at the origin? If yes, how much charge does it have? If no, explain why not. (2.5 points) y r X b. Calculate the strength and direction of the electric field a distance of 4.0 cm from the center. (2.5 points)b. Calculate the strength and direction of the electric field a distance of 4.0 em from the center. (2.5 points) c. Calculate the strength and direction of the electric field a distance of 9.0 cm from the center. (2.5 points) d. Calculate the strength and direction of the electric field a distance of 12.0 cm from the center. (2.5 points)