A Cubical Box Has Six Faces,each 20 Cm * 20

Multiple Choice

A cubical box has six faces,each 20 cm * 20 cm.The flux through each face is (the sides are labeled like a die,sides 1 and 6 are opposite to each other,as are 2 and 5,and 3 and 4. Side Flux (Nm²/C)
1 -120
2 + 300
3 -100
4 + 600
5 -40
6 -150
Find the net charge inside the cube.

A) 1.7 * 10^-10 C
B) 4.8 * 10^-10 C
C) 2.2 * 10^-9 C
D) 4.3 * 10^-9 C
E) More information is needed.