Why does the otter require oxygen to survive

They live and survive in the water's of streams, marshes, and other wet areas. But like any other mammal, they need to breathe to gain oxygen. ... Also, in the winter when the water freezes over the river otter is still able to breathe because it cuts small holes in the ice to get its head above water level.

Explanation:

if you add everything up correctly you should get 69 i got this because 50 plus 19 is it