When broadcasting was introduced in the 1920s, which two structural models were created that became dominant throughout the world?

The two structural models are radio and television broadcasting.

Explanation:

The two models fall under public broadcasting and where established during the 1920s and operated by the British broadcasting corporation which where a trusted organisation during the second world war. This models of broadcasting where later emulated by the whole of Europe.

Public broadcasting first started in Britain and other parts of the world used similar models as the one used in Britain. Modern broadcasting(radio and television models) has now gone commercial and is now a dominant form of transmitting information all over the world.

julius caesar turned the roman republic into the roman empire by coming in and taking the "dictator" role during the time of a civil war (elites vs lower classes) winning battles and reputation, then declaring him dictator for life

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