100 * pi = pi * r^2
Pi cancels on both sides of the equation
So... 100= r^2
= radius is 10
Answer:
Precambrian period
Step-by-step explanation:
Since the Great oxidation period = 2.4 Billion years ago era = Precambrian period.
Micro-fossils attributed to cyanobacteria are abundant during the Proterozoic that came later 2,5 billion years ago and ended 540 million years ago,
Answer:
the minimal number is 3
Step-by-step explanation: