Problem
1982 AHSME Problem 30
Find the units digit of the decimal expansion of
(15 + \sqrt{220})^{19} + (15 + \sqrt{220})^{82}.
\textbf{(A)}\ 0\qquad \textbf{(B)}\ 2\qquad \textbf{(C)}\ 5\qquad \textbf{(D)}\ 9\qquad \textbf{(E)}\ \text{none of these}
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