Figure shows a part of an electric circuit. The potentials at points \( a \), \( b \) and \( c \) are \( 30 \, \text{V} \), \( 12 \, \text{V} \) and \( 2 \, \text{V} \) respectively. The current through the \( 20 \, \Omega \) resistor will be:
\( 0.2 \)
\( 0.4 \, \text{A} \)
\( 0.6 \, \text{A} \)
\( 1.0 \, \text{A} \)
