The simplest and earliest method for determing the size of the earth uses

The answer is: comparing the Sun’s relative position at two different locations on the earth’s surface.

Explanation:

In the third century BCE , Eratosthenes, a Greek librarian in Alexandria , Egypt , determined the earth's circumference to be 40,250 to 45,900 kilometers (25,000 to 28,500 miles) by comparing the Sun's relative position at two different locations on the earth's surface.

Eratosthenes determined the earth's size by observing known phenomena and applying basic arithmetic and geometry to them. Here's how he did it. Eratosthenes' methods were simple but effective. All he needed to know was the distance between two locations and what percentage of a circle this distance constituted.

Iheard he was so amazing they named a whole city after him somewhere in california, absolute hero, they named a country in europe after him it’s called france, they just decided to change the o to an e because yknow, bants ennit

It just all depends on where you live at the moment