John F. Kennedy ran against c. Richard M. Nixon in the 1960 presidential election
A major contribution was was the development of the alphabet, roads, and more
One sentence that describes an example of social stratification during the Neolithic revolution may be: "<em>Hunting and gathering to farming". </em>
(It took many years, for humans to go from hunters and gatherers to a more common day life as we now know it, the result of this transition is referred to as the Neolithic Revolution, the beginnings of human civilization. This relatively stable way of life led to the development of new professions, to labour specialization and to the stratification of these societies.)
The Egyptians built irrigation systems in order to supply their crops with water.<span />
