Hello! I want to ask about why do we need to use Divergence Theorem in this question? Also, how does Divergence theorem help us solving this question? Can you answer as detailed as possible?

Thank you very much!

Calculate ff F - d where S F = (3": sin y, 3\"\" cos y, yz2) S is the surface of the box bounded by the planes x = 2, y = 5, z = 4, and the coordinate planes. 400 s/ o"