6. Non-contact Resistance (IYPT 2024)

This is a recording of a solution of Team Poland to the problem "6. Non-contact resistance" with the following wording:
The responses of a LRC circuit driven by an AC source can be changed by inserting either a non-magnetic metal rod or a ferromagnetic rod into the inductor coil. How can we obtain the magnetic and electric properties of the inserted rod from the circuit’s responses?