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Two charged balls are rigidly held in place 7.08 cm away from each other on a horizontal line. The ball on the left has a charge of q1=+3.43 microCoulombs. The ball on the right has a charge of q2=+7.72 microCoulombs. You now place a third ball with a charge of q3=+1.89 microCoulombs on the line connecting the first two balls such that q3 is between q1 and q2 and located exactly 2.7 cm to the right of q1. What is the magnitude of the net force on the charge q3? (Give your answer in units of Newtons.) {Helpful tip: A good first step should be to draw a figure] 3.41