PROBLEM $3$

In section $3\mathrm{.}3\mathrm{.}1$ of Module $4,$ the circuit known as the astable multivibrator, based on an OA$,$ is studied and reproduced in the figure. It is a circuit that does not have an input voltage $($except for the OA power supplies$),$ and it has an output Vo$.$ As you saw in the study materials, its function is to generate a square wave at the output, with a certain period determined by the value of its components.

We will power the OA with $$VCC $=15$ V from the available power supplies on the board, while the values of the other components are:

C$1=22$ nF$,$ R$1=100$ k$,$ R$2=56$ k$,$ R$3=56$ k$.$ a$)$

Find the theoretical period T that we expect the square wave at the output to have.