Why do federal system replace the confederal from of government that was first tried in the u. s

they are best known for the cliff pueblos found throughout arizona, new mexico, colorado and utah. and for their development of desert farming.

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-lavira: )

ww1 weapons: tank. tanks were used for the first time in the first world war at the battle of the somme. they were developed to cope with the conditions on the western front. the first tank was called 'little willie' and needed a crew of 3.