A point charge of +Q is placed at the centroid of an equilateral triangle. When
vi7h(i t;-o:kskv xv* a second charge of +Q is placed at one of the triangle's vertices, an electrostatic force of 4.0 N acts on it. What is the magnitude of the force that acts on the center charge due to a third charge of +Q placed
( kvi*kvix:ths-;7vo at one of the other vertices?