Explain how radioactive decay has always warmed the earth from the inside, and nuclear fusion has always warmed the earth from the outside.
A. The inner Earth is made of fissioning heavy elements, while the sun is made of lighter fusing elements.
B. Much heat was released as matter coalesced to form the earth. This heat resulted in the production of radioactive isotopes, which still reside within the earth today and are a source of internal heat. Our primary external source of heat is from the fusion of hydrogen within the sun.
C. Radioactive elements have been within Earth since it was created while the sun is made of fusing hydrogen atoms.
D. All of the above are reasonable answers.
Answer: C
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The ocean floor topography is
A. varied. B. unknown. C. smooth. D. flat.
Which of the following correctly states the connection between lithosphere age and water depth?
A) An older average lithosphere age corresponds with higher sea levels. B) An younger average lithosphere age corresponds with lower sea levels. C) An younger average lithosphere age corresponds with higher sea levels. D) There is no connection between average lithosphere age and sea level.
Most of the water on Earth can be found in ____
a. the atmosphere b. the ocean c. groundwater d. glaciers e. rivers and lakes
A typical wavelength of a tsunami is ________.
A. 100 to 200 m B. 10 to 20 m C. 100 to 200 km D. 1000 to 2000 km E. 1 to 2 m