How many times has CO2 exceeded 270 ppm in the past 450,000 years?
What will be an ideal response?
CO2 has exceeded 270 ppm five times in the past 450,000 years.
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Create a debate with the question; Do Canada and the United States have a moral and/or ethical responsibility to lead the world in addressing climate change?
What will be an ideal response?
Where is most of the world's pollution generated? This includes air pollution, water pollution, and solid wastes.
What will be an ideal response?
What is an intermontane physiographic region in North America?
A) Great Smoky Mountain range B) Rocky Mountain range C) basins, plateaus and small ranges in between mountains D) Mississippi-Missouri River system E) none of the above
When trying to recognize if a rock is metamorphic, why would a geologist not consider bedding?
A) Bedding in metamorphic rock is too complicated to study B) There is so much bedding in metamorphic rock to identify a rock by it. C) There are no obvious signs of bedding in metamorphic rock. D) Bedding indicates the presence of metamorphic minerals.