The boundary between the Archean and Proterozoic is marked by changes in ____
a. fossil assemblages
b. crustal evolution styles
c. atmospheric composition
d. oceanic composition
e. atmospheric temperatures
b
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How many degrees of longitude equals one hour of time?
a. 15? b. 24? c. 25? d. 45?
A stable population would remain at equilibrium if
A) the birth rate increased as the death rate decreased. B) emigration rates and death rates increased equally. C) births and immigration increased by the same quantity. D) births and deaths increased by the same quantity.
In 2010 India's total GDP was __________ in the world.
A. Fifth B. Fourth C. Second D. Sixth
Loss of part of the Earth's cryosphere will exert a positive radiative forcing effect on climate change because
A) more of the sun's radiation will be reflected into space. B) ocean thermal expansion will be increased. C) the overall albedo of the planet will be decreased. D) less carbon dioxide will be absorbed from the atmosphere by plants.