*7.69 In this problem we investigate the effect of the inevitable variability of β on the realized gain of the CE amplifier. For this purpose, use the overall gain expression in Eq. (7.114). G v = R L Rsig/β+1/gm where R L = RL RC. Consider the case R L = 10 k and Rsig = 10 k, and let the BJT be biased at I C = 1 mA. The BJT has a nominal β of 100. (a) What is the nominal value of Gv ? (b) If β can be anywhere between 50 and 150, what is the corresponding range of Gv ? (c) If in a particular design, it is required to maintain Gv within ±20% of its nominal value, what is the maximum allowable range of β? (d) If it is not possible to restrict β to the range found in (c), and the designer has to contend with β in the range 50 to 150, what value of bias current IC would result in Gv falling in a range of ±20% of a new nominal value? What is the nominal value of Gv in this case?