# In a common emitter transistor amplifier , the output resistance is $500 \;k \Omega$ and the current gain $\beta =49$ . If the power gain of the amplifier is $5 \times 10^6$, the input resistance is
$\begin{array}{1 1} 325\;\Omega \\ 165 \;\Omega \\ 240 \;\Omega \\ 225\;\Omega \end{array}$