All tetrapodes , mammals , birds , reptiles and amphibians .
Mammal
Yes, they are one of the classes of vertebrate.
yes
what two classes of vertebrates use external fertilisation
fish represent three of several classes that make up the phylum of vertebrate
Generally speaking, "beast" is simply another word for "animal" with four legs. It can be a vertebrate or an invertebrate. All animals are beasts. So, yes, an elephant is a beast.
The answer is a bed. A bed has four legs, it sits on the floor with its legs, and "waits" for someone's legs to come and lie down on it.
A tetrapod is a vertebrate animal with four limbs. "Tetra" means "four" and "pod" means "foot". Amphibians, reptiles, birds and mammals are all tetrapods; even snakes and other limbless reptiles and amphibians are tetrapods because they descended from animals which had four limbs. Whales and other cetaceans are also tetrapods because they are mammals have two front limbs and the two hind limbs are vestiges.
4 legs
mice have 4 legs :) look on google at pictures of them :p
-Name a vertebrate that has a 4-chambered heart -A hummingbird would be one good example of a vertebrate that has a four chambered heart.
A lion has four legs.