The major human causes of extinction today are
A. Poaching and habitat destruction
B. Pollution and invasive species
C. Global climate change
D. Both a and b
E. A, b, and c
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According to the data in the graph, what is true about oil versus coal and natural gas consumption?
A. the increase in natural gas consumption was greater than the increase in oil
B. oil consumption was not as high as natural gas or coal consumption
C. the spike in oil consumption beginning in 1963 resulted in an exponential increase over coal or natural gas consumption
D. the consumption of coal, oil, and natural gas all occured at the same rate
E. coal and natural gas consumption spiked over oil consumption in 1965
Which of the following provides the most renewable commercial energy in the world today?
A. solar
B. oil
C. biomass
D. nuclear
E. hydroelectric
Most alternative energy sources can be said to be derived either directly or indirectly from the sun. The exception to this is
A. geothermal
B. photovoltaic
C. biomass
D. corn based fuels
E. wind
What percentage of carbon is available for use in the world at the moment?
A. 5%
B. 25%
C. 50%
D. 90%
E. 100%
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