1) 2^(2n-1)=2^(2n)*2^(-1)=(1/2)*2^(2n)2) 5^(2n+1)=5^(2n)*5^(1)=5*5^(2n)3) 2^(2n-1)*5^(2n+1)=(5/2)*2^(2n)*5^(2n)=(5/2)*10^(2n)=(5/2)*100^(n)4) (2^(2n-1)*5^(2n+1))/(100^(n))=5/2
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