What is the phase difference between the input and output voltage for a common-base amplifier?

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

In an $NPN$ transistor,$10^{10}$ electrons enter the emitter in $10^{-6} \ s$ and $2\%$ of the electrons recombine with holes in the base. The current gains $\alpha$ and $\beta$ are respectively:

In the study of a transistor as an amplifier,if $\alpha = \frac{I_{C}}{I_{E}}$ and $\beta = \frac{I_{C}}{I_{B}}$,where $I_{C}$,$I_{B}$,and $I_{E}$ are the collector,base,and emitter currents respectively,then:

When a transistor is used as an amplifier in common emitter configuration,which of the following statements are correct?
$(1)$ The base-emitter junction is forward-biased.
$(2)$ The base-emitter junction is reverse-biased.
$(3)$ The input signal is connected in series with the biasing voltage to the base-emitter junction.
$(4)$ The input signal is connected in series with the biasing voltage to the base-collector junction.

In a transistor,the collector current varies by $ 0.49 \,mA $ and emitter current varies by $ 0.50 \,mA $. Current gain $ \beta $ measured is