A differential amplifier with signal terminals $X,Y,Z$ is connected as shown in Fig. (a) below for $CMRR$ measurement where the differential amplifier has an additional constant offset voltage in the output. The observations obtained are: when $V_i=2V, V_0=3mV,$ and when $V_i=3V, V_0=4mV$.
Assuming its differential gain to be $10$ and the op-amp to be otherwise ideal, the $\text{CMRR}$ is
- $10^2$
- $10^3$
- $10^4$
- $10^5$