Which gas comprises 20.9% of Earth's atmosphere?
a. oxygen
b. helium
c. argon
d. nitrogen
e. methane
a
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When we remove a pollutant from one part of the environment, it often ends up as a pollutant in another part of the environment.
Answer the following statement true (T) or false (F)
Which of the following are necessary for rainbows to appear?
A) rain falling at some distance away B) clear sky above the viewer C) clear sky behind the viewer D) all of these
What types of clouds and precipitation, if any, form when stable air is forced aloft?
What will be an ideal response?
Prior to WWII, what factor limited the development of large-scale industry in the Pacific Northwest?
A) The lack of power plants prevented the expansion needed. B) With the lack of population on the Pacific Northwest, there was no demand for finished goods. C) Its isolation from the rest of North America and difficulty of transporting goods. D) With the adult U.S. population depleted in the Pacific Northwest after WWI, there was a lack of workers available.