The usual problem that would frustrate attempting to organize entire world for the study is we do not know how many separate species of life forms that usually would exist on this planet. Hope this is the correct answer and this would help.
1s orbital
Explanation:
The electron has to go into the first energy level, in the 1s orbital. Helium, with two protons, will have two electrons. These are placed one at a time into the 1s orbital. This makes helium a very contented atom.
<span>The answer is : movement, reproduction, obtaining food and oxygen, and body structure</span>
Dog, cat,
Have hair
warm blooded
