14. When did cyanobacteria start producing pure oxygen? O A. After the Hadean eon
O B. During the Hadean eon
O C. After the Proterozoic eon
O D. During the Phanerozoic eon

All of the following statements about the biosphere are true except: a. light and heat from the sun do not affect the biosphere. b. the biosphere gets resources from earth's crust, hydrosphere and atmosphere. c. like "biology", the name for the biosphere comes from the greek word for life. d. the biosphere includes all living organisms on earth's surface.

Which of the following insects is a decomposer? a. mosquito. b. caterpillar. c. beetle. d. none of the above.

What factors influenced brazil's current and future economic strength?