Two long straight parallel wires are oriented in a north-south direction at the same height, 50.0 cm apart, and carrying currents of 8.00 A in opposite directions. Find the strength of the magnetic field (a) midway between the wires, (b) at a point in the plane of the wires but 3.00 m to the west of the "western" wire, and (c) at a point between and above the two wires, 10.0 m from each one.