Physics Question from JEE Main 2023 · 25 January, Shift 2

Two cells are connected between points A and B as shown. Cell $1$ has an emf of $12 \, \text{V}$ and internal resistance of $3\Omega$. Cell $2$ has an emf of $6 \, \text{V}$ and internal resistance of $6\Omega$. An external resistor of $4\Omega$ is connected across A and B. The current flowing through R will be _____ A.