An amplifier has a voltage gain $A_v = 1000$. The voltage gain in $dB$ is...........

The voltage gains of two amplifiers connected in series are $8$ and $12.5$. If the voltage of the input signal is $200 \mu V$, then the voltage of the output signal is

The correct curve between voltage gain $({A_v})$ and load resistance $({R_L})$ is

An oscillator is which of the following types of amplifier?

$A$ $p-n$ junction diode cannot be used

The amplifiers $X, Y$ and $Z$ are connected in series. If the voltage gains of $X, Y$ and $Z$ are $10, 20$ and $30$ respectively,and the input signal is $1 \, mV$ peak value,then what is the output signal voltage (peak value) $(i)$ if $DC$ supply voltage is $10 \, V$? $(ii)$ if $DC$ supply voltage is $5 \, V$?