the approximate age of earth is:

6,000 years

150,000 years

4.5 billion years

13.5 billion years
2.
on aristotle's scala naturae, humans were:

on the bottom rung

on the top rung

on the same rung as animals

lower than plants
3.
which of these ideas is not a central theory for modern biology?

evolution

creationism

cell theory

gene theory