In a closed loop non-inverting amplifier, constructed using single break-frequency op-amp, bandwidth with feedback can be written as. (f_{0} - break frequency, β - gain of the feedback circuit, A - open loop voltage gain, A_{f} - closed loop voltage gain)

A silicon sample A is doped with 10^{18} Atoms/cm^{3} of Boron. Another sample B of identical dimensions is doped with 10^{18} atoms/cm^{3} of phosphorus. The ratio of electron to hole mobility is 3. The ratio of conductivity of the sample A to B is