Answer:
Explanation:
It is estimated that the Precambrian Era lasted between 3.9 and 4 billion years. Many scientists believe that this era accounts for 90 percent of the world's history.
B
Publish his findings in a research journal because he is experimenting what medicinal properties can be tested or are associated with the plant. He should have kept the notes in a research journal for making observations so B.
I think genetic variation, but i'm not completely sure
Answer:
A
Explanation:
because cell theory states that living things are composed of one or more cells, that the cells is the basic unit of life, and that cells arise from existing cells.