To prevent the tipping point after which catastrophic environmental change will happen, what needs to be done?
A) Carbon dioxide emissions must be eliminated in the next two years.
B) Global greenhouse gas levels must peak no higher than 450 ppm and start declining by 2015.
C) All greenhouse gases need to immediately be reduced below their levels in 1990.
D) Carbon dioxide emissions must not rise more than 800 ppm, double the levels in the atmosphere today.
B
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The Colorado River is an example of a large wash
Indicate whether the statement is true or false
If a measured distance of 10 inches on a map represents an actual distance of 5 miles, what is the fractional scale of the map?
What will be an ideal response?
According to the Meteorological Service of Canada, which of the following defines a severe thunderstorm?
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