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**2. Homework Equations**

[tex]\Phi[/tex] = E[tex]\int[/tex]dA = [tex]\frac{q}{\epsilon}[/tex]

**3. The Attempt at a Solution**

I wasn't even sure how to start this problem. The fact that mass is given threw me off and I can't see how it would be used in the problem. I thought that possibly it could be used to find the electric force between the two objects since it must overcome the downward gravitational pull on the styrofoam (right?). From there, I used the equation that states F=qE to get that the magnitude of the electric field of the styrofoam is -1.4E5. Still, I have no idea how to find the charge per unit area of the plastic sheet and don't think my approach is anywhere near correct. Can someone please help me?