There are approx 100 billion
Answer:
The answer is number two extinction happened, this was the time dinosaurs went extinct ebcause lack of sun because oh how much dirt was blown into the earth atmosphere becuase of the asteriod, third option is talking about big bang theroy so that dosnt apply!
Explanation:
A = 70, B = 10, C=20, D=20, E= 30, F=50.
Take India for example.... people use the bathroom and bathe in rivers!
Now lets say we look at the US our pollution comes from factories, trash that people dont throw away, fertilizers and many more... but the difference is, that in developed countries like the US our water is filtered.... And in India water is not safe to drink