X is mathematically an unknown.
Answer:
4.54 billon years
Explanation:
the earliest time that life forms first appeared on Earth is at least 3.77 billion years ago possibly as early as 4.28 billion years
Answer: A Fixed Action Pattern
Explanation:
A fixed action pattern is an ethological term and off course a natural activity pattern that causes animals to act in a specific behavior pattern distinctive to their species. It is a pattern that is relatively unchangeable within the species and usually ends even when it is interrupted. You can say that, it is innate releasing mechanism or network where sign stimulus exists, once released from neural network; fixed action pattern leads to completion as well.
The answer would be kingdom
Answer:
b all the water on earth would freeze
Explanation:
if heat were not trapped in the atmosphere it would become very cold causing the earths water to freeze.
