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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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

The airborne material ejected from a volcano is termed________

A) lava B) magma C) silica D) granite E) pyroclastic material

Environmental & Atmospheric Sciences

Of the total energy intercepted at the Earth's surface and available for work, about 25% is fixed by photosynthesis as carbohydrates in plants

Indicate whether the statement is true or false

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