# When a battery connected across a resistor of $416 \Omega$, the voltage across the resistor is 12 V. When the same battery is connected across a resistor of $10 \Omega$, Voltage across it is 11V. The internal resistance of the battery in Ohms is

$\begin {array} {1 1} (1)\;\frac{10}{7} & \quad (2)\;\frac{20}{7} \\ (3)\;\frac{25}{7} & \quad (4)\;\frac{30}{7} \end {array}$

$(2) \frac{20}{7}$