An Infinitely Long Cylinder with a Radius of 1 $\rho$ = Ar, Where a = 10

An infinitely long cylinder with a radius of 1.0 cm has a charge density that is proportional to the distance from the axis of symmetry, $\rho$ = ar, where a = 10.0 C/m⁴. The electric field 0.50 cm from the central axis of the cylinder is

A) 1.4 $\times$ 10⁶ N/C.
B) 5.4 $\times$ 10⁶ N/C.
C) 9.4 $\times$ 10⁶ N/C.
D) 1.4 $\times$ 10⁷ N/C.