There can be a lot of factors that express sexuality. The origin would be its genes. The genetic make-up of the person what trait has passed on to an individual from his parents. Another factor is the environment. A person's sexuality can be influenced by social groups, home environment and from the media that he/she looks at.
Answer:
all of those can be included
Explanation:
Bacteria and birds both are organisms
Answer:
2.6 billion years old
Explanation:
Initial:
100% k-40
0% ar-40
After 1.3 billion years:
50% k-40
50% ar-40
After 2.6 billion years:
25% k-40
75% ar-40
So the rock is 2.6 billion years old.