Which of the following is not caused entirely or partially by human activities? Updated 1 hour ago:
A. The greenhouse effect

B. Global warming

C. Ozone

D. Smog

Rank the following from most to least devasting: ordovician,permaian,cretaceous, pleistocene

What was the atlanta race riot of 1906 ?

How did the mountains on the oregon trail influence the timing of pioneers’ travels? a.) the pioneers wanted to avoid times when there was snow in the mountains. the pioneers wanted to spend as much time as possible enjoying the mountain scenery. b.) the pioneers crossed the mountains in late fall when the trees were bare and the views were good. c.) the pioneers were rugged people who were not impacted by the terrain they crossed at any time.