**in $\mbox{m} \cdot \mbox{C}$** for a system of three charges ($Q=1~\mu \mbox{C}$, $Q=1~\mu \mbox{C}$, and $-2Q=-2~\mu \mbox{C}$) located on the vertices of an equilateral triangle of side $a=1~\mu \mbox{m}.$ One can show that for an electrically neutral system, the dipole moment is independent of the origin of coordinates (which makes this problem unambiguous).