A point charge of +Q is placed at the c
d571a.pcjtx t(xxt 4uppy 4 v*enter of a square, and a second point charge of -Q is placed at the upper-left co
t u5x44.pxyjc(7av t1t*d xpp rner. It is observed that an electrostatic force of 2.0 N acts on the positive charge at the center. What is the magnitude of the force that acts on the center charge if a third charge of -Q is placed at the lower-left corner?