Which region is the least doped in a transistor?

In a common emitter configuration, a transistor has $\beta=50$ and input resistance $1 \text{ k}\Omega$. If the peak value of a.c. input is $0.01 \text{ V}$, then the peak value of collector current is: (in $\mu\text{A}$)

If $R_C$ and $R_B$ are respectively the resistances of the collector and base sides of the circuit,and $\beta$ is the current amplification factor,then the voltage gain of a transistor amplifier in common emitter configuration is

For a transistor amplifier,the voltage gain:

In a $NPN$ transistor,the collector current is $24 \, mA$. If $80\%$ of electrons reach the collector,what is the base current in $mA$?

An $n-p-n$ transistor is biased to work as an amplifier. Which of the following statements is $NOT$ correct?