Explanation

(d) The given circuit can be simplified as shown below in circuit $R_{2},\ R_{5}$ and $R_{3},R_{4}$ are in series and then their resultant is connected parallel. Similarly $R_{7},R_{8}$ and $R_{6},R_{9}$ are in series and their resultant is connected parallel on simplifying this we get their equivalent circuit
[image:3_image158.emf]
Now current in circuit
$I = \frac{V}{R} = \frac{6}{3 \times 10^{3}\Omega} \times 10^{3} = 2mA$