The relative permeability of iron is $5500$. What will be its magnetic susceptibility?

Curie's law states that

According to Curie's law,the magnetic susceptibility of a substance at an absolute temperature $T$ is proportional to

Give the unit and dimensional formula of magnetisation.

An iron rod of cross-sectional area $2 \times 10^{-5} \ m^2$ is subjected to a magnetizing field intensity of $2000 \ A/m$. If the magnetic flux produced in the rod is $6.28 \times 10^{-4} \ Wb$,what is the magnetic permeability of the rod?

Define magnetisation $(M)$ and give its unit and dimension.