I'm not completely sure but I came up with Carbon dioxide, methane, water vapor, and nitrous oxide. I hope this is right and maybe helps you. Good luck!!
Answer:
Lizards / Reptiles
(Scientific four-legged snake is: Tetrapodophis)
Explanation:
couldn't add answer ^^ ignore comment :-)
Answer:
grass
Explanation:
grass produces the main source of energy for the food chain