A Spherical Shell of Radius 9 $\sigma$ = 90 NC/m²

Multiple Choice

A spherical shell of radius 9.0 cm carries a uniform surface charge density $\sigma$ = 9.0 nC/m².The electric field at r = 4.0 cm is approximately

A) 0.13 kN/C
B) 1.0 kN/C
C) 0.32 kN/C
D) 0.75 kN/C
E) zero