Name at least 5 groups that will be affected by fish depletion.

Well the reduction of fish will affects its consumers the animals that eat it for example: dolphins, bears, and toothed whales
It would also affect the things that fish eat it would become overpopulated because there would be no one who eats them to control their numbers example:
Shrimp, Algae and other things too
Hope this helps :)

Trident seafood
Cooke aquaculture
Mariah nichiro
Nippon suisan kaisha

The first method is simple division.

Answer is 786. Hope this helps.