Approximately ________ million years ago, the Earth began to have an oxygen rich atmosphere.
A. 359
B. 444
C. 250
D. 2500
Answer: D
Environmental & Atmospheric Sciences
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Indicate whether the statement is true or false
Environmental & Atmospheric Sciences
The Treaty of Guadalupe Hidalgo marked the end of the ________ and transferred ________ to the United States
Fill in the blank(s) with correct word
Environmental & Atmospheric Sciences
Differences in climate from one place to another at the microclimate level are almost always a result of human activity and have little to do with natural factors
Indicate whether the statement is true or false
Environmental & Atmospheric Sciences
The airborne material ejected from a volcano is termed________
A) lava B) magma C) silica D) granite E) pyroclastic material
Environmental & Atmospheric Sciences