The controls of most modern airplanes can be operated either manually or automatically.
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Formulatedin1823,theMonroeDoctrineassertedthattheAmericaswerenolongeropentoEuropeancolonization.
Thefirstpaperwasmadefromthebarkofthemulberrytree.
Although the Carbon 14 method of dating old objects is not foolproof , it is the best method available at present
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.