Six chargres are placed around a regular hexagon of side length a as shown in the figure . Five of then have charge q, and the remaining one has charge x, The perpendicular from each charge to the nearest hexagon side passes through the center O of the hexagon and is bisected by the side .

which of the following statement(s) is (are ) correct in SI units ?

Options

A. When x=q , the magnitude of the electric field at O is units ?
B. When x=-q , the magnitude of the electric field at O is ` (q )/(6 pi epsi_0 a ^2)`
C. when ` x= 2q` , the potential at O is `(7 q)/(4 sqrt(3 ) pi epsi_0 a)`
D. When `x=-3q` , the potential at O is `- (3q )/( 4 sqrt(3) pi epsi_0 a )`