how trading helped sparta economy?

Read widely and carefully and take good notes:

http://en.wikipedia.org/wiki/Trade
and
http://en.wikipedia.org/wiki/Trade#Prehistory
and
http://en.wikipedia.org/wiki/Trade#Development_of_money

Sparta - Wikipedia, the free encyclopedia
Sparta (Doric Σπάρτα; Attic Σπάρτη Spartē) or Lacedaemon, was a prominent city-state in ancient Greece, situated on the banks of the River Eurotas in ...
http://en.wikipedia.org/wiki/Sparta

Ancient Greece: Sparta
Jun 6, 1999 ... The rivalry, then, between Sparta and Athens, which would erupt into a disastrous war for Athens, was also an ideological and cultural ...
http://www.wsu.edu:8080/~dee/GREECE/SPARTA.HTM

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