Summarize the major differences between the Archean and Proterozoic. When did the
Proterozoic begin and end? What will be an ideal response?
The Proterozoic time unit began 2500 million years ago, and ended 542 million years ago.
Archean crustal evolution was dominated by the production of granite-gneiss complexes and
intervening greenstone belts; life originated in this time, and was exclusively prokaryotic. In the
Proterozoic, ophiolites and sandstone-carbonate-shale sequences indicate essentially modern
tectonic processes dominated by Wilson cycles. Proterozoic life started with prokaryotes, but the
eukaryotic cell developed, and multicelled life was present at the end of the Proterozoic.
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Steppe climates are found in areas of Brazil and:
A) Cuba B) Mexico C) Uruguay D) Haiti
Chlorine, Cl2, is a gas at room temperature, but bromine, Br2, is a liquid. Explain
A) Chlorine atoms are larger and this makes the formation of induced dipole-induced dipole attractions more favorable. B) Bromine atoms are larger and this makes the formation of induced dipole-induced dipole attractions more favorable. C) The smaller chlorine molecules are able to pack together in a tighter physical orientation. D) The bromine ions are held together by ionic bonds.
Snow line elevation increases with increasing latitude
Indicate whether the statement is true or false
Phil tosses a ball horizontally from a rooftop. One second after leaving his hand the ball's vertical component of velocity is about
A. 20 m/s. B. 10 m/s. C. 14 m/s. D. 5 m/s.