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

If the resistance $R_1$ is increased (see figure), how will the readings of the ammeter and voltmeter change?

In a common emitter amplifier circuit using an $n-p-n$ transistor,the phase difference between the input and the output voltages will be.....$^o$

Consider an $NPN$ transistor amplifier in common-emitter configuration. The current gain of the transistor is $100$. If the collector current changes by $1\, mA$,what will be the change in emitter current in $mA$?

In a junction transistor, the collector current changes by $6.8 \,mA$, if the emitter current is changed by $7 \,mA$. For such a transistor, the current amplification factor is

For a common emitter transistor,the current gain is $50$,the input resistance is $1 \ k\Omega$,and the input voltage is $0.01 \ V$. What is the collector current?