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3) As shown in the figure, a square insulating slab 5.0 mm thick measuring 2.00 m x 2.00 m has a charge of - 85 x 10-10 C distributed uniformly throughout its volume. Use Gauss's law to determine the electric field at point P (Magnitude and direction), which is located within the slab beneath its center, 1.00 mm from one of the faces. (80 = 8.85 x 10-12 C2/N . m2) 1.00 mm PO T 5.00 mm - 2.00 m