The figure shows a cross section across a long cylindrical conductor of radius a = 1.78 cm carrying uniform current 62.4 A. What is the magnitude of the current's magnetic field at radial distance (a) 0, (b) 1.33 cm, (c) 1.78 cm (wire's surface), (d) 2.71 cm? (a) Number Units (b) Number Units (c) Number Units (d) Number Units