Three spheres A, B, and C are placed in a line from left to right. Sphere B ( -5.0 μC\displaystyle \mu{C} ) is 30 cm to the right of sphere A (-5.0 μC\displaystyle \mu{C} ) and sphere C (+4.0 μC\displaystyle \mu{C} ) is 50 cm to the right of sphere B. What is the net force acting on sphere A?

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