A 12-M Radius Cylindrical Region Contains a Uniform Electric Field Along

Multiple Choice

A 1.2-m radius cylindrical region contains a uniform electric field along the cylinder axis.It is increasing uniformly with time.To obtain a total displacement current of 2.0*10 ^{- 9} A through a cross section of the region, the magnitude of the electric field should change at a rate of:

A) 5.0 V/m·s
B) 12 V/m·s
C) 37 V/m·s
D) 50 V/m·s
E) 4.0 * 10⁷ V/m·s