Because the costs of introducing recorded sound were low, it was the only innovation that was put to use in the 1920's. | The introduction of recorded sound prevented the development of other technological innovations in the 1920's. | The new technological and aesthetic developments of the 1920s included the use of color, new screen formats, and television. | Many of the innovations developed in the 1920s were not widely introduced until as late as the 1950's. |
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