Ninety percent of life's history in the geological time scale is occupied by the a. hadean eon. b. archean eon. c. proterozoic eon. d. precambrian supereon.

Which of the following can scientists estimate geologic time? a.observing rock sequences b.radiometric dating c.comparing fossils d.all of these

Which of the following statements best describes what is occurring in the land surrounding the sahara desert? a desertification is increasing, and the desert is expanding. b. fewer people are trying to farm in this semiarid region. c. the desert is shrinking with the increased use of irrigation. d. increased urbanization has resulted in decreased deforestation. select the best answer from the choices provided mark this and return save and exit next submit

Which mountain range separates georgia from russia? a. ural mountains b. carpathian mountains c. caucasus mountains d. siberia mountains