= Solution
\b[The diagnostic <infrared spectroscopy> absorptions are the conjugated <ester> carbonyl near $1720\,\mathrm{cm^{-1}}$ and the <alkene> stretch near $1650\,\mathrm{cm^{-1}}$.] Reasonable approximate ranges are $1715$–$1730$ and $1620$–$1660\,\mathrm{cm^{-1}}$, respectively. <Conjugated system> lowers the carbonyl stretching <spectroscopic wavenumber> relative to an unconjugated <ester>.
The <ester> C–O stretches and strong C–F stretches lie mainly in the $1000$–$1300\,\mathrm{cm^{-1}}$ region. Vinylic C–H stretching is just above $3000\,\mathrm{cm^{-1}}$, and saturated C–H stretching is about $2850$–$3000\,\mathrm{cm^{-1}}$. There is no <hydroxy group> to give a broad O–H band.
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