Which gas was not a part of earth's atmosphere 3.6 billion years ago?

Which of the following regions has what is considered the most rugged terrain in oklahoma? a. the wichita mountains b. the arbuckle mountains c. the sandstone hills d. the ouachita mountains

What are the secondary main characters in aquaman?

Compared with the land in the highlands, the lowlands region of england a) rockier and more difficult for farmingb) the center of business and industryc)richer in coal reservesd)covered by more fertile farmland d) covered by more fertile farmland