(a) Design an inverting op-amp circuit with a closed-loop voltage gain of \(A_{v}=-6.5\). When in the input voltage is \(v_{I}=-0.25 \mathrm{~V}\), the magnitude of the currents is to be \(50 \mu \mathrm{A}\). Determine \(R_{1}\) and \(R_{2}\).

(b) Using the results of part (a), find \(v_{I}, i_{1}\), and \(i_{2}\) when \(v_{O}=-4.0 \mathrm{~V}\).