What is the continental shelf?

The continental shelf is an underwater ledge around the coastline of the world’s oceans.

The edge of the shelf lies at depths of between 360 and 480 feet.

The width may vary from a few feet to several hundred miles.

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Did Betsy Ross design the American flag? No, it was designed by Francis Hopkinson, a naval flag designer, who was never reimbursed for his services by the U.S. government. And there is no record of Betsy Ross's commission to sew…
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