The Anwser is 3 all you have to do is put 4-25$ and that gives you the anwser which is 3 i hope this helps you
I believe it’s that they made it a democracy :) hope this helps !
Assuming the cube is closed, you can use the divergence theorem:
where is the surface of the cube and is the region bounded by .
We have
so the flux is 0.
All of them are wrong except for the third one