How did industries increase productivity in the 1920s? build factories in foreign nations
formed monopolies and trust
increase the efficiency of workers
obtained new resources, technologies, and machinery

(you can select multiple choices)

Option: obtained new resources, technologies, and machinery

Explanation:

Industries in 1920 increased their productivity for several reasons, including new machinery which transforms the cities. In 1920 more industries were coming up. Technologies were developing rapidly, which led to rapid economic growth. Locomotives helped in supplying raw materials and transport goods at an affordable price and in less time. Assembly lines play a role in 1920 by increasing productions.

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