\HCode{<\a:mathml mover accent="false"\Hnewline
\mml:class="mml-overline"><\a:mathml mrow>}%
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\HCode{</\a:mathml mrow><\a:mathml mo\Hnewline
accent="true">&\#x00AF;</\a:mathml mo>%
</\a:mathml mover>}%
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\HCode{<\a:mathml munder \a:mathml accentunder="false"\Hnewline
\mml:class="mml-underline"><\a:mathml mrow>}%
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\expandafter\everymath
\expandafter{\expandafter\everymath
\expandafter{\the\everymath}}%
\let\o::@underline:\o:@@underline:
\def\o:@@underline:{\let\o:@@underline:\o::@underline:}%
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\HCode{</\a:mathml mrow><\a:mathml mo\Hnewline
accent="true">&\#x0332;</\a:mathml mo></\a:mathml munder>}%
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<style:style style:name="underline" style:family="text">
<style:text-properties style:text-underline-style="solid"
style:text-underline-width="auto"
style:text-underline-color="font-color"
/>
</style:style>
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Overline??
<style:style style:name="overline" style:family="text">
<style:text-properties style:text-underline="dotted" />
</style:style>
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