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! Undefined control sequence.
<argument> \FBafil \unvbox \@currbox
                                     \FBbfil
l.50 \end{figure}

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! Missing number, treated as zero.
<to be read again>
                   \vfill
l.50 \end{figure}

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[40]

! LaTeX Error: \begin{document} ended by \end{figure}.

See the LaTeX manual or LaTeX Companion for explanation.
Type  H <return>  for immediate help.
 ...

l.50 \end{figure}