Two coplanar and concentric circular loops of wire carry currents of I1 = 6.20 A and I2 = 2.50 A in opposite directions as in the figure below. (a) If r1 = 12.0 cm and r2 = 8.60 cm, what is the magnitude of the net magnetic field at the center of the two loops? 1 µT (b) If r1 = 12.0 cm and r2 = 8.60 cm, what is the direction of the net magnetic field at the center of the two loops? 2 out of the page into the page toward the top of the page toward the bottom of the page .. (c) Let r1 remain fixed at 12.0 cm and let r2 be a variable. Determine the value of r2 such that the net field at the center of the loop is zero. r2 = 3 cm