A cylindrical region of radius R=3.0 cm contains a uniform magnetic field parallel to its axis. If the electric field induced at a point R/3 from the cylinder axis is 4 × 10^-3 V/m the magnitude of the magnetic field must be changing at the rate.
(a) 0
(c) 0.60 T/s
(b) 0.20 T/s
(d) 1.2 T/s