When carbon is added to iron in the proper proportions , the result is steel.
D
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Themegaphone(microphone)makesthevoicesoundlouderbecauseitpointssoundwavesinonedirectionandkeepsthemfromspreadingoutinalldirections.
Formerly,intheUnitedStates,manynursesworkedasprivatedutynursesratherthaninhospitals.
Bythenineteenthcentury,embroideryonmen'sclothinghadvirtuallydisappearedexceptfortheoccasionaldecorativevestandtie.