The vertices $V$ of a centrally symmetric hexagon in the complex plane are given by $V=2i,-2i,\frac{1}{2}(1+i),\frac{1}{2}(-1+i),\frac{1}{2}(1-i),\frac{1}{2}(-1-i)$. For each $j$, $1\le j\le 10$, an element $z_j$ is chosen from $V$ at random, independently of the other choices. Let $P={\prod }_{j=1}^{10}{z}_j$ be the product of the 10 numbers selected. What is the probability that $P=-2$?