From September 2013 to March 2014 there were 2830 cases of scarlet fever in the UK
From September 2014 to March 2015 there were 5943 cases of scarlet fever.
Calculate the percentage increase of the number of cases of scarlet fever between
the periods September 2014 to March 2015 and September 2013 to March 2014.

in 1859, charles darwin set out his theory of evolution by natural selection as an explanation for adaptation and speciation. he defined natural selection as the "principle by which each slight variation [of a trait], if useful, is preserved".

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