no
All mammals use lungs to breath.
No, they must surface to breathe, as they have lungs like all mammals.
Whales are mammals and must breath air. If they cannot reach the surface to breath they will drown.
All mammals breathe with lungs.
No they take the oxygen in the water through their gills. However, whale do because they are mammals not fish and all mammals need to breath after all humans don't have gills do they?
Gills are found in a number of animals. Most notably in all types of fresh and salt water fish but also mollusks like snails and slugs. Crustaceans like crab and lobster have them to as do a number of insects and amphibians such as frogs, lizards and worms.
Marine Mammals have a very large lung capacity which allows them to hold their breaths from 25 minuets with the average seal to over 2 hours with the sperm whale. They breath when they breach or come out of the water in jumps or just sticking their blow holes out of the water.
The all breath under water They all have fins,gills,scales,breathe under water,swim. ;D
Are you serious? the same way that all other mammals do using their respiratory tract under the control of the autonomic nervous system
Emus are not mammals, and are therefore not the same as other mammals at all. Emus are birds.
Porpoises have a blowhole they have to open and close when emerging and submerging in water. Also, when underwater, they're not breathing at all, they're holding their breath. Porpoises have to consciously breathe. Its not a natural, second nature thing to do like most mammals, due to the fact that they hold their breath and don't constantly breathe in and out like other mammals that live out of the water.
Yes, dolphins are mammals. Dolphins are endothermic, breath air and nurse their young like all other mammals.