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(a) Design a low-pass OP AMP circuit to pass only the fundamental and the next nonzero harmonic of a 20π ms square wave. The gain of the OP AMP should be +5.

(b) Find the first four nonzero terms in the Fourier series of the output of your filter.

(c) Validate your design using Multisim. The OP AMP’s VCC = ± 15 V.