In what form is the energy stored in an inductor?

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 energy stored in an inductor of self-inductance $L$ henry carrying a current of $I$ ampere is:

$A$ solenoid of inductance $2 \ H$ carries a current of $1 \ A$. What is the magnetic energy stored in the solenoid (in $J$)?

The magnetic energy stored in an inductor of inductance $4 \ H$ carrying a current of $1.5 \ A$ is

Assertion : If the current in a solenoid is reversed in direction while keeping the same magnitude,the magnetic field energy stored in the solenoid remains unchanged.
Reason : Magnetic field energy density is proportional to the magnetic field.