Answer:
they came up with irrigation which showed later civilizations ways to help them farm they also built the first city in the world. they made a language for others to use. they also made Hammurabi's code for other civilizations to use. made the first ever potential number system. they made the wheel and chariot.
Explanation:
The answer is d: Ford's revolution of the assembly line to make cars less expensive.
although they saw he invented the assembly line he did not it was in fact Ransom E. Olds who did. all that Ford did was improve it. he put a person to do one thing and that was what they did nothing else. this made it faster as to this had nobody fighting to do the job with the person they were working with.
United states, United Kingdom, Canada, Brazil, Russia, Pakistan, India, France, Denmark, Japan, South Korea. There are many more
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one quarter of GDP.
That is the correct answer! Hope this helps!