D*2.117 This problem illustrates the use of cascaded closed-loop amplifiers to obtain an overall bandwidth greater than can be achieved using a single-stage amplifier with the same overall gain. (a) Show that cascading two identical amplifier stages, each having a low-pass STC frequency response with a 3-dB frequency f1, results in an overall amplifier with a 3-dB frequency given by (b) It is required to design a noninverting amplifier with a dc gain of 40 dB utilizing a single internally compensated op amp with ft = 2 MHz. What is the 3-dB frequency obtained? (c) Redesign the amplifier of (b) by cascading two identical noninverting amplifiers each with a dc gain of 20 dB. What is the 3-dB frequency of the overall amplifier? Compare this to the value obtained in (b) above.