In a transistor,the value of $\beta$ is $50$. The value of $\alpha$ is ........

When an $NPN$ transistor is used as an amplifier,which of the following occurs?

In a common base circuit of a transistor,the amplification factor is $0.95.$ The base current when the emitter current is $2\,mA,$ is ....$mA$

$A$ transistor is used as an amplifier in $CB$ mode with a load resistance of $5 \, k\Omega$. The current gain of the amplifier is $0.98$ and the input resistance is $70 \, \Omega$. The voltage gain and power gain respectively are:

For transistor action:
$(1)$ Base,emitter and collector regions should have similar size and doping concentrations.
$(2)$ The base region must be very thin and lightly doped.
$(3)$ The emitter-base junction is forward biased and base-collector junction is reverse biased.
$(4)$ Both the emitter-base junction as well as the base-collector junction are forward biased.
Which one of the following pairs of statements is correct?

While a collector to emitter voltage is constant in a transistor,the collector current changes by $8.2 \,mA$ when the emitter current changes by $8.3 \,mA$. The value of forward current ratio is