How was the Olmec society able to grow into cities and eventually a civilization?

Trading helped the Olmec build their urban centers of San Lorenzo and La Venta. These cities, however, were used predominantly for ceremonial purposes and elite activity; most people lived in small villages. Individual homes had a lean-to—sort of like a garage shed—and a storage pit for storing root vegetables nearby.

Explanation:

equal area projections

equal-area projection. a projection in which regions on the earth's surface that are of equal area are represented as equal.

"this speech"? what speech are you talking about?