The answer is Perspectives, they taught themselves about different perspectives to help them put depth into their artwork.
The correct answer should be<span> President Kennedy pushed the Civil Rights Act through Congress and signed it into law.
He didn't manage to finish it however because of the assassination, but there was incentive and he used the public sentiment to get people to support his ideas. After his death, Lyndon B. Johnson managed to finish putting the Civil Rights Act into law. </span>
The reason is <span>Because the gramophone used discs instead of foil cylinders.
This allows Gramophone to </span><span>anaged to press thousands of copies from a sole matrix,. This ability makes Gramophone managed to perform 25 times more effieicnt than the phonograph which makes the phonograph starte to lose its popularity.
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