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Cornell University

Cornell University: Astronomy: Eratosthenes

For Students 9th - 10th
Learn how Greek mathematician Eratosthenes used geometry to estimate the circumference of the Earth.
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Mocomi & Anibrain Digital Technologies

Mocomi: What Is Circle?

For Students 2nd - 8th
Discusses the radius, diameter, circumference, and area of a circle.
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University of St. Andrews (UK)

University of St. Andrews: Eratosthenes of Cyrene

For Students 9th - 10th
Gives details of the accomplishments of Eratosthenes in the field of mathematics.
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National Institutes of Health

Nih: Aim for a Health Weight

For Students 9th - 10th
This brief but informative site discusses the role of body mass index and waist circumference in determining your risk of disease and death.

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