Question

calculate the total number of years that each geological eras lasted, rounding to the neareast 100 million, Then, calculate each of these values as a percentage of the total 4.6 billion years of Earth History. Round your answer to the units place.

Answer 1

Explanation:

Cenozoic = 100 mil years (rounded) = 66 real

Mesozoic = 200 mil years (rounded) = 174 real

Paleozoic = 300 mil years (rounded) = 330 real

Cenozoic = 100mil/4.6bil = .0217 (x100 for percentage) = 2%

Mesozoic = 200mil/4.6bil = .0435 (x100 for percentage) = 4%

Paleozoic = 300mil/4.6bil = .0652 (x100 for percentage) = 7%