The primary difference between barter and currency systems is that a currency system uses an agreed-upon form of paper or coin money as an exchange system rather than directly trading goods and services through bartering.
The Indus River of course provided for a direct source of water in the region, which helped sustain life, but it also provided for wide-spread irrigation of the surrounding land, which made for very fertile soil and healthy crop growth. Another benefit to this region was the temperate climate.
rhineland was invaded by Germany in 1936
They do chemical examination to see how old is an artefact. Also based on previous objects, which were already dated by using a comparison can be determinated if the object is newer or older.
In addition, the scientist dig all the time so based on the excavations they make a thesis about what the live in this place was. If the same objects are found in another country for example , that means this people have traveled.. etc
The railroad was a big step to transportation and helped the growth
