Which of the following statements is incorrect?

Two inductors $L_1$ (inductance $1 \text{ mH}$,internal resistance $3 \text{ } \Omega$) and $L_2$ (inductance $2 \text{ mH}$,internal resistance $4 \text{ } \Omega$),and a resistor $R$ (resistance $12 \text{ } \Omega$) are all connected in parallel across a $5 \text{ V}$ battery. The circuit is switched on at time $t=0$. The ratio of the maximum to the minimum current $(I_{\max} / I_{\min})$ drawn from the battery is:

Radio frequency choke uses a core of

In the circuit shown below,all the inductors (assumed ideal) and resistors are identical. The current through the resistance on the right is $I$ after the key $K$ has been switched $ON$ for a long time. The currents through the three resistors (in order,from left to right) immediately after the key is switched $OFF$ are

The current $i$ in an inductance coil varies with time $t$ according to the following graph. Which one of the following plots shows the variations of voltage $V$ in the coil?

The plane of a circular coil of resistance $7.5 \ \Omega$ is placed perpendicular to a uniform magnetic field. The flux $\phi$ (in weber) through the coil varies with time $t$ (in second) as $\phi = 2t^2 + 3t - 2$. The induced power in the coil at time $t = 3 \ s$ is (in $W$)