Suppose the emitter areas of the BJTs of Fig. P4.75 are such that AE1 5 AE2 5 0.5AE3, and all three BJTs have VA 5 75 V. (a) Assuming negligible base currents, specify suitable values for R1 and R2 so...

Suppose the emitter areas of the BJTs of Fig. P4.75 are such that AE1 5 AE2 5 0.5AE3, and all three BJTs have VA 5 75 V. (a) Assuming negligible base currents, specify suitable values for R1 and R2 so that, with VC 5 0.7 V the circuit gives IC3 5 1 mA and IC2 5 20 A. (b) If we increase VC above 0.7 V, what is the percentage change in IC3 and IC2 for every 1-V increase in VC?