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6 Cards in this Set
- Front
- Back
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what has happened to the man hours over the last 250 yrs
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shortened-taking less time
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what caused the man hours to decline
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new mechanization
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what has happened to the crop yields over the last 250 yrs
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yields have increased
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what has caused the yields to increase
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chemicals being used
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why did the farmers start using silos, what did this signal
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farmers were growing more crops
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American agriculture changes in the last 15-20 yrs
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more technology (computers)
GPS GMO's |
