Since 1990, average ________ levels in the US have consistently been below the national standard
A) CO
B) ozone
C) PM10
D) CO and PM10
Answer: D
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Which of the following states has the lowest earthquake risk?
A. Nevada B. South Carolina C. Massachusetts D. Florida E. Arkansas
The Hubbard Glacier in North America is an example of which kind of glacier?
A) Valley B) Ice Sheet C) Piedmont D) Cirque
How does deforestation by fire or human activity contribute to mass wasting?
A) It allows the wind to blow across the slopes, imparting a stress that triggers landslides. B) It kills tree roots that help hold the slopes in place, allowing mass movement. C) It allows farming activity that exposes soil to erosion and mass wasting. D) It allows excess rainfall runoff to erode the landscape, triggering mass wasting.