https://www.chegg.com/homework-help/questions-and-answers/calculate-flux-vector-field-f-14xyi-7y-2j-k-surface-s-figure--apply-divergence-theorem-clo-q17533207

https://www.chegg.com/homework-help/questions-and-answers/let-w-region-figure-bounded-cylinder-x2-y2-4-plane-z-x-1-xy-plane-use-divergence-theorem-c-q17687079