A point charge of 2.5 [nC] is positioned in the middle of a hollow conducting spherical shell, which has an outer surface charge of 7.5 [nC] and an inner surface charge of -2.5 [nC]. The spherical shell has inner and outer radii of 0.02 [m] and 0.03 [m], respectively. Evaluate using Gauss's Law and draw the situation:

a) The electric field at r = 0.01 [m] from the center.

b) The electric field at r = 0.025 [m] from the center (i.e., inside the shell).

c) The electric field at r = 0.05 [m] from the center.