The biogeochemical cycles are considered to have been in a planetwide steady-state condition for the last ________ years.
A) ten
B) one thousand
C) one million
D) one billion
E) one trillion

Question

Quizplus · Accepted Answer

The biogeochemical cycles have been considered to be in a planetwide steady-state condition for the last one billion years, reflecting the long-term stability and balance of these cycles on Earth over geological time scales.

The Biogeochemical Cycles Are Considered to Have Been in a Planetwide