Two coils A and B have 180 and 360 turns respectively. The current of 1A flows through both the coils. Due to current of 1A in coil A, flux per turn of $0.8 \times 10^{-3}$ Wb is linked with coil A. Due to current of 1A in coil B, flux per turn of $1 \times 10^{-3}$ Wb is linked with coil B. The self inductance of coil A is $L_A$ and the self inductance of coil B is $L_B$. The ratio $L_A$ to $L_B$ is

If current of 4 A produces magnetic flux of $3 \times 10^{-3}$ Wb through a coil of 400 turns, the energy stored in the coil will be

The equivalent inductance between A and B is equal to

In the circuit shown, when the current '$i$' is $3\text{A}$ and increasing at the rate of $1\text{A/s}$ the measurement of the potential difference between A and B is $12\ \text{V}$. But when the same current $3\text{A}$ is decreasing at the rate of $1\text{A/s}$, the measured potential difference $V_{AB}$ between A and B is $6\text{V}$. The value of 'R' in the circuit is