Question 1128727
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The meaning of the question that is asked is uncertain, because the language makes no sense:<br>
"By how many trees does forest B over forest A after 20 years?"<br>
It appears we are to find how many more trees are in forest B than forest A after 20 years.  But forest B initially has fewer trees than forest A, and the rate of increase for forest B is smaller -- so forest B will never have more trees than forest A.