Of the four types of Thematic maps, it is the CHLOROPLETH MAP which is ranked classes of some variable are represented using colored or shaded patterns and placing of symbols for those zones that are predefined. This is to show the average value of a certain property.
A fall line is an upland region of the coastal plains meets and the term states that lots of rivers fall from this Piedmont to the coastal plain making rapids with waterfalls.
These falls are important as for the settlement as they block the ocean going ships from entering in any further upstream and also provided water power to run the region industries.
