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CD School House 9
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CD School House 9.0 - Wayzata Technology (1994).iso
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acecalc
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descrip.dat
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l05.dal
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1994-02-18
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The heat required to maintain these temperatures is derived from the natural
radioactivity of the earth's constituent rocks. After 4.6 billion years the
earth's internal heat is still a source of mechanical power, producing
earthquakes and volcanic eruptions, raising mountains, and moving continent-
sized blocks about its surface.
$
MARS
The landscapes of Mars are basically desert vistas strewn with rocks ranging up
to several metres wide. Judging by their texture and color and chemistry
analysis, the rocks are fragments of lava flows. The soil composition
resembles that of basaltic lavas on earth and our moon. About 1% of the soil
is water, chemically bound in the crystal structure of the rock and soil
particles. Some planetary scienticsts speculate that water in the form of
permafrost exists a few metres below the surface. Water was once abundant
enough on Mars to leave major structures on the planet resembling riverbeds,
likely carved during the planet's early history.
The red planet's thin atmosphere has an average surface pressure only 0.7% of
earth's and consists of 95% carbon dioxide, 2.7% nitrogen,