In what form is the energy stored in an inductor?

The energy stored in a $50 mH$ inductor carrying a current of $4 A$ is (in $J$)

In an inductor of inductance $L = 100 \, mH$,a current of $I = 10 \, A$ is flowing. The energy stored in the inductor is ....... $J$.

The magnetic potential energy stored in a certain inductor is $64 \times 10^{-3} \ J$,when the current in the inductor is $80 \ mA$. The inductance of this inductor is: (in $H$)

An inductor may store energy in

The expression for the magnetic energy per unit volume stored in a solenoid in terms of magnetic field is . . . . . . .