Apoint charge with a charge q1 = 3.60 μc is held stationary at the origin. a second point charge with a charge q2 = -4.60 μc moves from the point x= 0.100 m , y= 0 to the point x= 0.250 m , y= 0.250 m .how much work w is done by the electric force on the moving point charge?