The sum of the squares of the first $n$ natural numbers is

$A_n=1^2+2^2+$cdots$+n^2$ and the square of the sum of

the first $n$ natural numbers is $B_n=(1+2$cdots$+n{)}^2.$ Let

$C_n=B_n-A_n.$ For example, $A_{10}=385$ and $B_{10}=3,025.$

Then $C_{10}=3,025-385=2,640.$ What is $B_{100}-A_{100}?$