The decay of 40K has a half of 1.3 × 109 years. The age of the earth is estimated at 4.6 × 109 years. The decay of 40K is a major heat source for the earth's interior
Relative to today, how much more heat was produced by 40K in the early Archaeon era or 3.9 × 109 years ago?
A) 8x B) 4x C) 2x D) 6x
A
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What type of volcano is made up of alternating layers of ash, cinder, and lava?
a. a cinder cone b. a composite volcano c. a cone of depression d. a dome e. a shield volcano
The study of the origin and arrangement of the broad structural features of Earth's surface is
A. tectonics. B. structuralism. C. geology.
How does the shift in sea-surface temperatures correspond to the seasons
in the Northern and Southern Hemispheres? What will be an ideal response?
List the different weather elements provided on a station model. Then describe how sea level pressure is given, the notation system for denoting cloud cover, and a general description of how wind speed and direction are indicated
What will be an ideal response?