Which of the following provides the most renewable commercial energy in the world today?
A. solar
B. oil
C. biomass
D. nuclear
E. hydroelectric
查看答案
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%
What is the largest source of stored carbon?
A. atmosphere
B. continental lithosphere
C. oceanic lithosphere
D. groundwater
E. trophosphere
Which of the following shows a change in the carbon cycle due to based on human impacts?
A. decrease in carbon dioxide in the atmosphere
B. increase in carbon dioxide in the oceanic lithosphere
C. increase in carbon dioxide in the continental lithosphere
D. increase in carbon dioxide in the atmosphere
E. decrease in carbon dioxide in the oceanic lithosphere
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