Question

How do petroleum refineries act as 'nodal industries'?

Answer 1

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Industries that are responsible for providing ingredients for other manufacturing units are called Nodal industries.

Answer 2

#nodal industries are the industries which provide ingredients to other manufacturing industries are known as nodal industries 

#as the petroleum refineries provide their products as raw material to industries like synthetic industries, fertilizer and numerous chemical industries and thus called as nodal industry

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