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I'm having problems with the following question:

Neutral metal sphere A, of mass 0.10 kg, hangs from an insulating wire 2.0 m long. An identical metal sphere B, with charge -q, is brought into contact with sphere A. The spheres repel and settle as shown. Calculate the initial Charge on B.

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B----- A

The formula for Coulomb's law is F(e)= (kq1q2)/r^2, where k is a constant of 9.0 X 10^9 Nm^2/C^2

I tried finding the force of gravity for A, using Fg=mg, and i ended up getting 0.98 N (down). Using, tan, I found the force between BA to be 0.2083 N, and i assumed that this is the F(e). I used sin to find the distance (separation) between BA, and i got 0.4158 m. I plugged this information into Coulomb's formula and i got q= 2.0 X 10^-6 C, which is wrong. Please tell me what I did wrong.