**Question:**

For the circuit shown, with $\mathrm{R}_{1}=1.0 \Omega, \mathrm{R}_{2}=2.0 \Omega, \mathrm{E}_{1}=2 \mathrm{~V}$ and $E_{2}=E_{3}=4 \mathrm{~V}$, the potential difference between the points ‘ $a$ ‘ and ‘ $b$ ‘ is approximately (in V) :

Correct Option: 4

**Solution:**

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