Question: A solid sphere of radius 55.0 cm is concentric with a spherical shell of radius 78.4 cm. The solid sphere has a charge of -98.5 x 10-7 C on it, and the outer shell has a net charge of +98.5 x 10-7 C on it.
Question I: The surface charge density on the outer shell is?
mC/m2.
Please also explain, thank you in advance.