The Figure Shows a Group of Three Particles, All of Which

The figure shows a group of three particles, all of which have charge $Q = 8.8 \mathrm { nC }$ . How much work did it take to assemble this group of charges if they all started out extremely far from each other? $( k$ $\left. = 1 / 4 \pi \varepsilon _ { 0 } = 9.0 \times 10 ^ { 9 } \mathrm {~N} \cdot \mathrm { m } ^ { 2 } / \mathrm { C } ^ { 2 } \right)$
$3.0 \mathrm {~cm}$

A) $5.9 \times 10 - 5 \mathrm {~J}$
B) $5.7 \times 10 ^ { - 5 } \mathrm {~J}$
C) $6.2 \times 10 ^ { - 5 } \mathrm {~J}$
D) $5.5 \times 10 - 5 \mathrm {~J}$