fish
I do not know of any mammal (mammals are the only animals to have hair) that has fins (fins are the preserve of fishes), but a sea-lion is an animal that is covered in hair and has "flippers".
a fish
A reptile?
The animal that has two pairs of fins is the bony fish, specifically those belonging to the class Actinopterygii. Most bony fish possess a pair of pectoral fins located on the sides of their bodies and a pair of pelvic fins located further back, both of which help with swimming and maneuverability. These fins are essential for balance and stability in the water.
4 fins
2 fins
Animals that use fins to move are whales, dolphins, sharks, and various types of fish. A fin will generate thrust and propel the animal through the water.
seven fins are on a sailfish.
there are none.
These are structural. They're to do with an animal's structure. Behavioural means to do with how an animal behaves, or responds.
There are two Dorsal fins on a perch. The anterior and posterior Dorsal fins.
fins, tails, and any other appendages really.