Approximately how many years ago did the last continental ice sheet retreat from New York State? A) less than 1 million years B) 2.5 million years C) 1 billion years D) 10 billion years

The correct answer is A) Less than 1 million years

Explanation:

A continental ice sheet is a massive layer of ice that covers thousands of kilometers. Nowadays, these can only be found in zones such as Antarctica but millions of years ago these were more common. Indeed, a continental ice sheet known as the Laurentide ice sheet covered Canada, Greenland, and some zones in the U.S. including New York, this ice sheet first formed around 2.5 million of years ago and changed over time as this covered more or less kilometers due to growth and melting cycles. However, around 20,000 years ago the ice sheet began to definitely retreat due to higher temperatures, and now is reduced to Greeland. Thus, this ice sheet retreat from New York State less than 1 million years ago because it occurred between 20,000 and 8,000 years ago.

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