Final answer:
Ferromagnetic substances have high permeability and high susceptibility.
Step-by-step explanation:
Ferromagnetic substances have high permeability and high susceptibility.
Permeability refers to the substance's ability to support or amplify an existing magnetic field, and ferromagnets have a high permeability, meaning they can greatly enhance an external magnetic field.
Susceptibility refers to the extent to which a material can be magnetized by an external magnetic field, and ferromagnetic materials have a high susceptibility, meaning they can easily be magnetized and exhibit strong magnetic effects.