A circular wire coil consists of 100 turns and is wound tightly around a very long iron cylinder with a radius of 2.5 cm and a relative permeability of 2200. The loop has a current of 7.5A in it. Determine the magnetic field strength produced by the coil (a) at the center of the coil and (b) at a location on the central axis of the iron cylinder 5.0 cm above the center of the circular coil.

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