The magma that is high in silica usually forms light colored such as granite and the lava that is in low silica usually forms in a dark colored rocks such as basalt. I hope this helped you.
<span>D.He had two terrorist centers bombed in retaliation.
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Okay, so, just from the top of my head, I think that it is because of the growing belief of "Manifest Destiny" in the nineteenth century. I'm not sure if this is the actual right answer for your question, but I do know that Manifest Destiny was in the nineteenth century and was the widely held belief in the USA that American settlers were destined to expand through out the continent. And I think both the USA and Europe wanted to expand, it was kind of a copetition/conflict they had. This was actually how Canada and Alaska came to be I believe. This was a simple explanation btw. cx
Option 'B' = changes in climate, had the greatest impact on pre-historic man.
Changes on the weather forced men to move periodically or cyclically, usually returning to their original location at various times. When they moved to colder climates, they would make clothing out of animal skins, to protect themselves. When the nomads learned how to plant, they didn't need to search for other places anymore.
