What was the primary reason that a fourth sector of the economy was created? the increase in population the increase in demand for trade work the digital revolution the industrial revolution

What was the primary reason that a fourth sector of the economy was created? The digital revolution. The digital revolution began in the late 1950's through the 1970's. The digital revolution is known as the Third Industrial Revolution and was brought about when there was a shift from mechanical and analogue electronic technically to digital technology. The use of digital computers and recording became a wide spread hit and is still being used today. 

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