7.55 Consider the augmented hybrid-π model shown in Fig. 7.26(a). Disregarding how biasing is done, what is the largest possible voltage gain available for a signal source connected directly to the base and a very-high-resistance load? Calculate the value of the maximum possible gain for VA = 20 V and VA = 120 V.
VA = 20 V: −800 V/V; VA = 120 V: −4800 V/V