$A$ paramagnetic substance is placed in a non-uniform magnetic field,then

Which of the following statements is true in respect of diamagnetic substances?

When a ferromagnetic material is heated to a temperature above its Curie temperature,the material

Magnetic susceptibility of $Mg$ at $300 \ K$ is $1.2 \times 10^{-5}$. What is its susceptibility at $200 \ K$?

$A$ paramagnetic sample shows a net magnetisation of $6 \, A/m$ when it is placed in an external magnetic field of $0.4 \, T$ at a temperature of $4 \, K$. When the sample is placed in an external magnetic field of $0.3 \, T$ at a temperature of $24 \, K$,then the magnetisation will be $...... \, A/m$.

Provide information about electromagnets.