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10.18 An ideal voltage amplifier having a voltage gain of –1000 V/V has a 0.1-pF capacitance connected between its output and input terminals. What is the input capacitance of the amplifier? If the amplifier is fed from a voltage source Vsig having a resistance Rsig = 10 kΩ, find the transfer function Vo/Vsig as a function of the complex-frequency variable s and hence the 3-dB frequency fH and the unity-gain frequency ft. 100.1 pF; ;159 kHz; 159 MHz