All whales have to live at the top at some point. They breathe air.
The killer whale (Orca) is the top predator of the ocean.
The blue whale is the fastest, the sperm whale is not far behind and the right whale is the slowest. The blue whale would be the only one with a well defined fin (a dorsal fin) on it's back. A sperm whale (like all toothed whales and dolphins) has a single blowhole at an angle on the top/front part of its head, so it has a single blow that comes up at an angle. A right whale (like all baleen whales) has a double blowhole on the top of its head. It has a double blow. A blue whale, even though it also has a double blowhole has a high and straight blow. There are several good field guide books that show the difference between the blows of different types of whales.
Gray whales are baleen whales. The Sperm whale is the only really big toothed whale.
Humans/great white sharks/Killer whales/Manatee/Whales
Not many predators can kill whales, but small and young whales often fall as victims to killer whales, one of the top predators of the ocean. Humans also hunt whales for their body parts or for food, often illegally.
Dinoflagellates live in the top 200 feet of the ocean.
Killers whales. They eat practically everything (cetaceans, sirenians, pinnipeds, sea otters, sea turtles, sharks, rays, bony fishes, squid).
You would have to define how you are comparing them. Whales are mammals and sharks are fish. They are both top predators, they both swim in the ocean, have fins and share a lot of other things, but have a lot of differences also.
Yes. Their name is, actually, reversed, as they are "whale killers", known to separate calves from the pod & hold it underwater until it drowns. Then they eat it. They are the world's oceans top predator, even as humans are the world's land top predator.
squid, um.... that's all i can think of off the top of my head.
Dolphins are one of the top predators in the ocean, but they do have a few predators. The shark and the killer whales are two of their main enemies.
they live at both. some live on the bottom and some are exsposed