Eratosthenes was the first person to accurately estimate the size of Earth.He accomplished this feat by ________.
A)sailing around the world and estimating his average rate of travel
B)comparing the length of an Earth day with the distance between the Earth and the Sun
C)measuring the severity of the greatest earthquakes
D)observing shadows simultaneously cast at two different cities that were separated by a known distance

Question

Quizplus · Accepted Answer

Eratosthenes measured the angle of the Sun's rays at noon on the summer solstice at two different locations and calculated the circumference of the Earth using the distance between the two locations. This was possible because he knew the distance between the two cities and assumed that the Earth was a sphere.

Eratosthenes Was the First Person to Accurately Estimate the Size