A bridge circuit is connected to an ideal battery of electromotive force \(\mathcal{E} = 12\text{ V}\), as shown in the diagram. Resistors \(R_1 = 2.0\text{ }\Omega\) and \(R_2 = 6.0\text{ }\Omega\) form the left branch, while resistors \(R_3 = 6.0\text{ }\Omega\) and \(R_4 = 2.0\text{ }\Omega\) form the right branch. A central resistor \(R_5 = 3.0\text{ }\Omega\) connects node \(a\) between \(R_1\) and \(R_2\) to node \(b\) between \(R_3\) and \(R_4\). What is the magnitude of the electric current flowing through resistor \(R_5\)?