Bc

Christ was born in 4 BC.

Newton thought the world had been created in 4000 BC.

In 508BC, the ruler of Athens, Cleisthenes established ostracism to prevent the appearance of a tyrant.

Let H be the base of the perpendicular drawn from point A to the line BC.

Thales used the astronomical records of the Babylonians and Egyptians to accurately predict a solar eclipse in the sixth century BC.

Aristotle, who lived from 384 to 322 BC, believed the Earth was round. He thought Earth was the center of the universe and that the Sun, Moon, planets, and all the fixed stars revolved around it.

In the 100s BC, Hipparchus, the most important Greek astronomer of his time, calculated the comparative brightness of as many as 1,000 different stars. He also calculated the Moon's distance from the Earth.

Cotton may have been used in India as long ago as 3500 BC, and in Peru as long ago as 3000 BC.

Hippocrates in 400 BC said that exercise is man's best medicine, but his message has been lost over time and we are an increasingly sedentary society.

The Roman Republic was founded in 509 BC.