The megaphone(microphone) makes the voice sound louder because it points sound waves in one direction and keeps them from spreading out in all directions.
B
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Thefirstpaperwasmadefromthebarkofthemulberrytree.
Formerly,intheUnitedStates,manynursesworkedasprivatedutynursesratherthaninhospitals.
DoubleEagleinthefirsttransatlanticballoon,wasgreetedbyavidcrowdsinFrance.
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Formulatedin1823,theMonroeDoctrineassertedthattheAmericaswerenolongeropentoEuropeancolonization.