A very large nonconducting plate lying in the xy-plane carries a charge per unit area of 9. A second such plate located at z = 2.65 cm and oriented parallel to the xy-plane carries a charge per unit area of −4. What is the electric field at a point between the two plates?
a) 0 N/C
b) 4 N/C
c) 9 N/C
d) -9 N/C