Lines of Charge: the Cross Section of a Long Coaxial

Lines of charge: The cross section of a long coaxial cable is shown in the figure, with radii as given. The linear charge density on the inner conductor is and the linear charge density on the outer conductor is The inner and outer cylindrical surfaces are respectively denoted by A, B, C, and D, as shown. The radial component of the electric field at a point that 34 mm from the axis is closest to

A) - 16,000 N/C.
B) + 16,000 N/C.
C) - 37,000 N/C.
D) + 37,000 N/C.
E) zero.