<span>Good Morning!
The specialization of work is as old as the first human groupings, and it was through division by sex. The invention of the wheel dates from at least 2000 years before Christ, and can be extended up to 3,500 years if we take into account the first illustrations of a wheel. The controlled use of fire, in turn, dates back more than a million years, while the development of agriculture is about 10,000 years old. Thus, among the discoveries and inventions pointed out. It is worth noting, however, that the invention of the wheel, while important, would not contribute to such a large population growth.
Agriculture (letter d), gradually improved from 5,000 BC, is the fundamental factor for population growth, which could now settle, rather than live as a nomad.
Hugs!
</span>
The core has the largest density, being made of iron and nickel
The mantle has an intermediate density and the crust has the lowest density.
Educated people don't need to be in Iran. Iran doesn't provide colleges or any type of higher education that awards degrees. Iran is also a dangerous place, especially for women, seeing as you have gangs or terrorist groups such as The Taliban or Isis.
Gorges are narrow/skinny valleys between hills or mountains that often have a stream or river running through it. Waterfalls are rivers that stop and drop vertically into another body of water.
Hope this helped :)