= Solution
At a <carbon-13> resonance <frequency> of $75\,\mathrm{MHz}$, the three resolved <NMR coupling constants> are
$$
\begin{aligned}
{}^1J_{\mathrm C_e\mathrm F}&=(127.48-123.90)75=\boxed{268.5\,\mathrm{Hz}},\\
{}^2J_{\mathrm C_f\mathrm F}&=(132.04-131.57)75=\boxed{35.25\,\mathrm{Hz}},\\
{}^3J_{\mathrm C_g\mathrm F}&=(129.09-129.01)75=\boxed{6.0\,\mathrm{Hz}}.
\end{aligned}
$$
Each is the spacing of adjacent lines within its own quartet. The lower panel of the original coupling diagram in 1(b)(ii) marks the corresponding carbon–<fluorine> interactions. The bond superscripts count bonds along the connecting path; they are not additional numerical factors multiplying $J$.
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