Eratosthenes can be credited with being the 'first person' to calculate the 'circumference of the earth'.
<u>EXPLANATION:</u>
Eratosthenes measured the circumference of the earth by noting the 'angle of shadows' in two cities on 'summer solstice' and by performing calculations using his knowledge and geometry.
He lived in Alexandria which was in North Egypt.
He used Alexandria and Syene, a city in South Egypt for calculating the angle of shadow made on summer solstice because he knew that the 'sun was never overhead' in Alexandria even on summer solstice.
He measured the distance between the 'two cities' and applied geometry for calculating the 'circumference of the earth' in stadia which was a unit of measurement used at that time.
