In the figure, two long straight wires at separation d = 20.7 cm carry currents of i1 = 2.20 mA and i2 = 8.00 i, out of the page. (a) At what coordinate on the x axis in centimeters is the net magnetic field due to the currents equal to zero? (b) If the two currents are doubled, is the zero-field point shifted toward wire 1, shifted toward wire 2, or unchanged? (a) Number Units (b)