Ptolemy was an astronomer and mathematician. He believed that the Earth was the center of the Universe. The word for earth in Greek is geo, so we call this idea a "geocentric" theory.With the development of the heliocentric model by Nicolaus Copernicus in the 16th century, the Sun was believed to be the center of the Universe, with the planets (including Earth) and stars orbiting it.
The net electrical charge of the earth
C. Upward; downward. As the hot rock rises, cooler rock flows downward to take its place next to the core, where it is heated and becomes buoyant enough to rise again later
A frame shift mutation is the shift of the genetics of an object.
This type of mutation os caused by the insertion or deletion of nucleotides in a DNA sequence that is not divisible by three.
