What is the power gain in a $CE$ amplifier,where the input resistance is $3\,k\Omega$ and the load resistance is $24\,k\Omega$,given $\beta = 20$?

In $n-p-n$ transistor, in $CE$ configuration:

In an $npn$ transistor,$10^{10}$ electrons enter the emitter in $10^{-8}$ second. If $1\%$ of electrons are lost in the base,the fraction of current that enters the collector and the current amplification factor are respectively:

$A$ $n-p-n$ transistor is connected in common-emitter configuration in which the collector supply is $8\, V$ and the voltage drop across the load resistance of $800\,\Omega$ connected in the collector circuit is $0.8\, V$. If the current amplification factor $\alpha$ is $25/26$,the collector-emitter voltage $V_{CE}$ and the base current $I_B$ will be:

In an $NPN$ transistor,if the doping in the base region is increased,then the collector current:

In a common emitter transistor,the current gain is $80$. What is the change in collector current,when the change in base current is $250 \ \mu A$?