Hello!
I don't know how this is being measured, so i'm not adding measurement values to the answer. qwq
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Your Answer
In 1996, the Appalachian produced the most coal, with it's number being 452.
In 2011, the Western produced the most coal, with it's number being up to 588.
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Explanation
According to the chart, in 1996, the Appalachian produced an amount of coal, with its number being 452. According to 2011 stats, however, the Western area produced an amount of coal, with it being 588. That's a difference of 136.
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Hopefully this helps 'ya out! °ω°
( Could 'ya mark as Branliest answer pls? .w. )
~Spider
