2001 AMC 10 Problems/Problem 5

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Problem

How many of the twelve pentominoes pictured below have at least one line of symettry?

$\textbf{(A)}\ 3 \qquad \textbf{(B)}\ 4 \qquad \textbf{(C)}\ 5 \qquad \textbf{(D)}\ 6 \qquad \textbf{(E)}\ 7

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Solution