[21.5] Electric-Field Calculations: A uniform line of charge with length 20.0 cm is along the x-axis, with its midpoint at x=0. Its charge per length is +4.80 nC/m. A small sphere with charge -2.00 μC is located at x=0,y=5.00 cm. What are the magnitude and direction of the force that the charged sphere exerts on the line of charge?