Taxonomy is the classification of things; organisms.
Hope this helps.
The answer is the first one because it doesn't create gases and, the third one doesn't even make any sense so its definitely not that one
Answer:
Mammals first appeared
Explanation:
The dinosaurs became extinct one million years after the Cenozoic era started. The mammals first appeared as the modern culture first appeared in that era.
Answer:
A. Chipmunks sleeping underground through the winter
Explanation:
A seasonal change in the behavior of a living organism is a change that occurs every year at a particular time. The reasons for the occurrence of such changes are so that the organism has advantage in survival in the environment. In this case we have the chipmunk that sleeps underground through the winter. We have an animal which exhibit a seasonal change every year, during the winter period. The reason for this is that the chipmunks have very quick metabolism, so if they are active during the winter they will starve because of lack of food. Instead, the chipmunks have evolved to hibernate during the winter, thus slowing down the work of their hurt during the winter and sleep, until the spring comes.
Yes it can kill brain cells. if you hold your breath for a short amount of time example 10 seconds it won't do any harm. but if you hold your breath for an extended time like a minute the cells will not get enough oxygen and eventually die. I hope I helped you