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(9) A spherical metallic object with a concentric hole inside initially holds a net charge of q1 = -3.60 nC. Then a particle with a charge of 92 = 2.98 nC is placed at the center of the hole (held by a thin perfect non-polarizable insulating material); see the figure below. The value of the net charge on the outer surface of the conductor, upon reaching electrostatic equilibrium, is most nearly 91 91 =? 92