Which civilization created the earliest known solar observatory?

Mesopotamia

Explanation:

It was created about 7000 years ago by one of Europe's oldest civilization, long before the cultures of Mesopotamia and the pyramids of Egypt.

mount st. helens in washington erupts, causing a massive avalanche and killing 57 people on this day in 1980. ash from the volcanic eruption fell as far away as minnesota. seismic activity at mount st. helens, which is 96 miles south of seattle, began on march 16.

d. a week

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