A Small Sphere of Mass 2

A small sphere of mass 2.5 × 10^-5 kg carries a total charge of 6.0 × 10^-8 C. The sphere hangs from a silk thread between two large parallel conducting plates. The excess charge on each plate is equal in magnitude, but opposite in sign. If the thread makes an angle of 30° with the positive plate as shown, what is the magnitude of the charge density on each plate?

A) 2.5 × 10^-9 C/m²
B) 5.2 × 10^-9 C/m²
C) 1.0 × 10^-9 C/m²
D) 2.1 × 10^-8 C/m²
E) 4.2 × 10^-8 C/m²