Answer:
Kr, mass number 81, number protons 36.
Explanation:
If the atom has 36 electrons, and it is neutral, it has 36 protons. 36 protons means that this element has atomic number = 36. This is Kr.
Mass number = number protons + number neutrons = 36 + 45 = 81
Answer:
Populations have genetic variation.
The environment changes.
Organisms must have specific traits in order to survive and reproduce.
Explanation:
Natural selection is a phenomenon whereby organisms better adapted to their environment are able to survive due to this phenotypic capability.
- Natural selection provides an advantage during an adverse condition for organisms that have a rich genetic variation in their population.
- Also, environmental changes induces natural selection whereby organisms must adapt to changes around.
- For organisms to survive, they must have specific traits that gives them a competitive reproductive advantage.
They are far apart from one another and they move around alot
I would say it is B because when u pull ur leg up the space in your muscles are smaller when you spread your leg out they relax because they are not pulling anything.<span />
