Horses, donkeys, mules, pigs, cattle, sheep, goats, chickens, large dogs, cats and bees were rapidly adopted by native peoples for transport, food, and other uses.
Answer is B, the railroad system going through the cities.
To combat the creation of NATO, the USSR (AKA Russia and multiple other nations) banded together with its communist counterparts and signed a pact in Warsaw, hence the alliance's name, "Warsaw Pact."
<span>A. A rebellion of Greek city-states against Persia, which was the impetus for the Greco-Persian Wars.</span>
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