A14.8-g piece of styrofoam carries a net charge of -0.742 µc and is suspended in equilibrium above the center of a large, horizontal sheet of plastic that has a uniform charge density on its surface. what is the charge per unit area on the plastic sheet?

a charge 3q is at the origin, and a charge −2q is on the positive x axis at x=a. part a where on the x-axis would you place a third charge so it would experience no net electric force? enter an expression for the exact answer, which will involve a square-root sign. (do not enter an approximate decimal answer.)

which statement about this sum is true? −245+2.7