Using the series-shunt amplifier shown in Fig. 31.56, (a) identify the feedback topology by labeling the mixing variables and output variable, (b) verify that negative feedback is employed, (c) draw...

Using the series-shunt amplifier shown in Fig. 31.56, (a) identify the feedback topology by labeling the mixing variables and output variable, (b) verify that negative feedback is employed, (c) draw the closed-loop small-signal model, and (d) find the expression for the resistors R_BI
and R_BO
.