What is an obelisk how tall is it

Although the earliest obelisks were a little over 3 meters tall, or about 10 feet, they gradually became taller, reaching about 30 meters, or around 100 feet, in height.

A tapering stone pillar, typically having a square or rectangular cross section, set up as a monument or landmark. Usually about 10m high.

isaac newton first proposed that earth was not perfectly round. instead, he suggested it was an oblate spheroid—a sphere that is squashed at its poles and swollen at the equator.

the idea of the earth being a flat disc is also inconsistent with the fact that a given lunar eclipse is only visible from half of the earth at a time. the only shape that casts a round shadow no matter which direction it is pointed is a sphere, and the ancient greeks deduced that this must mean the earth is spherical.

the world may never know