ball in equilibrium when string in 16.3 angle w/vertical whats net charge on ball? acc. 9.8 and the Coulomb8.98755×109Nm2/C2 Answer units µC?

The geometry of the string gives us the geometry of the forces:

tanΘ = electrostatic force / weight

So, you're missing some data here. First, you need the mass of the ball in order to calculate the weight.

Second, you need the field strength (F = q*E where E is the field).

If you can take it from here, great; if not, please update your question with more data. Hope this helps!

I was not given the mass of the ball or the field strength. Please help