All living organisms, regardless of their unique identity, have certain biological, chemical, and physical characteristics in common.
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Themegaphone(microphone)makesthevoicesoundlouderbecauseitpointssoundwavesinonedirectionandkeepsthemfromspreadingoutinalldirections.
AlthoughtheCarbon14methodofdatingoldobjectsisnotfoolproof,itisthebestmethodavailableatpresent
ThefirstimportantexpositionintheUnitedStateswasheldinPhiladelphiain1876.
In1861itseemedinevitablethattheSouthernstateswouldbreakawayfromtheUnion.