For the circuit shown in the figure below, it is given that $${V_{CE}} = {{{V_{CC}}} \over 2}.$$ The transistor has $$\beta = 29$$ and $${V_{BE}} = 0.7\,\,V$$ when the $$B$$-$$E$$ junction is forward biased.

For this circuit, the value of $${{{R_B}} \over R}$$ is

The circuit shown in the figure uses matched transistors with a thermal voltage $${V_T} = 25\,mV.$$ The base currents of the transistors are negligible. The value of the resistance $$R$$ in $$k\Omega $$ that is required to provide $$1\,\,\,\mu A$$ bias current for the differential amplifier block shown is ____________.

The voltage gain $${A_V}$$ of the circuit shown below is