(a) $A = \frac{\mu R_{L}}{r_{p} + R_{L}} = \frac{14 \times 12}{10 + 12} = \frac{84}{11}$. Peak value of output signal $V_{0} = \frac{84}{11} \times 2\sqrt{2}V$
$\Rightarrow V_{rms} = \frac{V_{0}}{\sqrt{2}} = \frac{84 \times 2}{11}V$
$\Rightarrow r.m.s.$ value of current through the load
$= \frac{84 \times 2}{11 \times 12 \times 10^{3}}A = 1.27\ mA$