Answer:
The color is considered dark if the rock appears as a dark gray to black (pyroxenes, the amphibole Hornblende, the mostly Ca-plagioclases near Anorthite, and Biotite mica. Density is a property that is proportional to the composition of the rock. The higher the amount of silica (felsic) the less dense the rock will be.
Explanation:
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Answer:
d) cutting a larger crystal along four perfect cleavage planes, forming a cleavage fragment.
Explanation:
Fluorite Octahedron crystals are formed narutally, <em>but it's not common,</em> they can be found more commonly as cubes,<em> the majority of fluorite octahedron are formed when miners cit them along its natural cleave lines. </em>
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Answer:
it is said that the Ice Ages began 2.4 million years ago and ended approximately 11,500 years ago.
Explanation:
During this time Carbon-Dioxide (a poisonous and warming gas) levels rose dramatically by about 180 ppm to 280 ppm.
This caused the major retreat of glaciers that ran across continents...
There were other gases but they were in VERY small amounts...
(APART FROM OXYGEN)
<span>La biotecnología es un área multidisciplinaria, que emplea la biología, química y procesos, con gran uso en agricultura, farmacia, ciencia de los alimentos, ciencias forestales y medicina. Probablemente el primero que usó este término fue el ingeniero húngaro Karl Ereky, en 1919.</span>