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In this first look, the focus regarding top-quark physics was on precision measurements of the top-quark mass, width and Yukawa coupling through a scan of the ${\rm t\bar t}$ production threshold, with $\sqrt{s}$ comprised between~340 and~350\,GeV. The expected precision on the top-quark mass is in turn used, together with the outstanding precisions on the Z peak observables and on the W mass, in a global electroweak fit to set constraints on weakly-coupled new physics up to a scale of 100\,TeV. Although not studied in the first look, measurements of the top-quark electroweak couplings are of interest, as new physics might also show up via significant deviations of these couplings with respect to their standard-model predictions. Theories in which the top quark and the Higgs boson are composite lead to such deviations. The inclusion of a direct measurement of the ttZ coupling in the global electroweak fit is therefore likely to further constrain these theories.   It has been claimed that both a centre-of-mass energy well beyond the top-quark pair production threshold and a large longitudinal polarization of the incoming electron and positron beams are crucially needed to independently access the tt$\gamma$ and the ttZ couplings for both chirality states of the top quark. In Ref.~\cite{Baer_2013}, it is shown that the measurements of the total event rate, the forward-backward asymmetry, and the helicity asymmetry of the top quark with 500\,${\rm fb}^{-1}$ at $\sqrt{s}=500$\,GeV and with beam polarizations of ${\cal P} = \pm 0.8$, ${\cal P}^\prime = \mp 0.3$, allow for this distinction. The aforementioned claim is revisited in the present study. The sensitivity to the top-quark electroweak couplings is estimated here with an optimal-observable analysis of the lepton angular and energy distributions from ${\rm t\bar t}$ production in the $\ell \nu {\rm q \bar q b \bar b}$ final states (with $\ell = {\rm e}$ or $\mu$) at the FCC-ee, without incoming longitudinal beam polarization and with a centre-of-mass energy not significantly above the ${\rm t\bar t}$ production threshold. Such a sensitivity can be understood from the fact that the moderate top-quark polarization arising from its coupling to the Z is maximally transferred to the final state particles via the weak top-quark decay ${\rm t \to W b}$ with a 100\% branching fraction: the lack of initial polarization is compensated by the presence of substantial final state polarization, and by a larger integrated luminosity. A similar observation had already been made many years ago at LEP, with the measurement of $\sin^2\theta_W$ from the $\tau$ polarization in ${\rm Z} \to \tau^+\tau^-$ events~\cite{Altarelli:1989hv}.