Identify the locations on the x-axis where the magnetic field is zero when there is a setup involving a long wire with a 7.0 A current intersecting the x-axis at x = -3.0 cm and another parallel wire with a 4.0 A current intersecting the x-axis at x = +3.0 cm? Consider both scenarios: (i) when the currents flow in the same direction, and (ii) when the currents flow in opposite directions.