Potential due to a system of charges and work done

2022 Phase 2 1 question

1. Six charges $+q$, $-q$, $+q$, $-q$, $+q$ and $-q$ are fixed at the corners of a hexagon of side d as shown in the figure. The work done in bringing a charge $q_0$ to the centre of the hexagon from infinity is: ($\varepsilon_0$ - permittivity of free space)