Answer:
You either are referring to the fish Chordate, or the animal classification. In the case of the classification it is literally any animal that has developed any sort of dorsal fin, for example some snakes can fall under this classification.
It’s either carbon or hydrogen but I would definitely go with hydrogen
Answer:
two
Explanation:
The endocrine and central nervous systems are the major control systems for regulating homeostasis
Sorry i dont understand spanish and please translate in english please