In the ac equivalent circuit shown in the figure, if i$${_F}$$ is very large, the type of feedback is

In the circuit shown, the op-amp has finite input impedance, infinite voltage gain and zero input offset voltage. The output voltage V_out is

In the low - pass filter shown in the figure, for a cut - off frequency of 5 KHz, the value of R₂ (in k$$\Omega $$ ) is _________

In a code - division multiple access (CDMA) system with N = 8 chips, the maximum number of users who can be assigned mutually orthogonal signature sequences is _______.