Consider a Cubical Box That Contains a Charge Distribution of Total

Consider a cubical box that contains a charge distribution of total charge q = 6.40 $\mu$ C.The total electric flux through 5 of the 6 sides is $\varPhi$ = 3.90 *10⁵ Nm²/C.What is the electric flux through the remaining sixth surface of the box (in Nm²/C) ?

A) 3.33 * 10⁵
B) 3.90 * 10⁵
C) 4.56 * 10⁵
D) 5.34 * 10⁵
E) 6.24 * 10⁵