Hello everyone, I am trying to get some homework help on the following question attached below. If someone could show me how to solve it step by step, that'd be greatly appreciated. Thanks!

4. For the op-arnp circuit shown in Fig 4: a. Find the differential equation for the circuit output, V0 (t), in terms of R1, R2 and R3 if Vs = u(t). b. Find the solution for the zero-state response, V0 (t). c. What is the expression for the time constant of the circuit? d. If the resistances are constrained to values between 0 and 1 k9, which resistance (R1, R2 or R3) is the time constant most sensitive to, such that it changes the most as this resistance changes. Show your reasoning. e. Let R1 = R2 = R3 = R and sketch the response of Vo(t)