Answer:Both technicians
Explanation:
Magnetic permeability refers to the degree of magnetic flux established within a material by a magnetising field divided by the actual field strength. Materials that have high magnetic permeability allow lines of force to pass through them easily. Some insulator materials do not allow magnetic flux to flow through them easily while some do allow it. Those insulators that allow magnetic field to pass through them are called magnetic insulators e.g Fe2O3 and some other transition metal oxides.