The circuit in figure 32-34 consists of switch S, a 20.0MΩ resistor, a 12.0V ideal battery, and an air filled capacitor. The capacitor has parallel circular plates of radius 5.00 cm, separated with 3.00 mm. At time t =0, switch S is closed to begin charging the capacitor. The electric field among the plates is uniform. At t =250 μs, what is the magnitude of the magnetic field within the capacitor, at radial distance 3.00 cm?