= Solution
\b[TODO: a numerical estimate from the missing MINOS spectrum cannot be supplied.] On source page 7 the graph is absent: PDF Form /Im3 invokes undefined image /Im1 with no image resources, and the archived bundle has the same defect. In particular, no measured minimum <energy> survives. For maximal <mixing angle>, the first minimum of <muon neutrino> survival obeys
$$
1.27|\Delta m^2|\frac{730}{E_{\min}}=\frac\pi2,\qquad
|\Delta m^2|[\mathrm{eV}^2]=1.6943\times10^{-3}E_{\min}[\mathrm{GeV}].
$$
A restored spectrum or fitted data are needed to choose $E_{\min}$. This is a relation for the survival minimum; a minimum in the raw event spectrum also depends on flux, <cross section> and smearing. For context only, accelerator and atmospheric results put the splitting at a few $10^{-3}\,\mathrm{eV}^2$, versus the solar splitting about $7.5\times10^{-5}\,\mathrm{eV}^2$, roughly thirty times smaller. This known scale is not a reconstruction of the absent graph. <Combined analysis of muon-neutrino disappearance and electron-neutrino appearance by MINOS Collaboration>[MINOS combined three-flavour analysis, 2014]{ref}
Finite event statistics, <hadronic shower> <energy resolution>, the <muon> scale, near-to-far flux extrapolation, interaction and nuclear modeling, backgrounds and detector calibration limit the precision; the baseline itself is comparatively well known. In a two-flavour vacuum fit the sign of $\Delta m^2$ is inaccessible. Evidence for dominant $\nu_\mu\to\nu_\tau$ includes the zenith-angle-dependent atmospheric deficit in <Super-Kamiokande>, approximately preserved active <neutral current> rates, small electron-flavour appearance at this scale, atmospheric tau appearance and direct tau appearance in <OPERA>. The latter had already reported four candidates and $4.2\sigma$ evidence in 2014; a later five-candidate discovery result is not needed for this June 2015 answer. <Observation of tau neutrino appearance in the CNGS beam by OPERA Collaboration>[OPERA tau-appearance result, 2014]{ref} These tests constrain a dominant sterile conversion as well as conversion into <electron neutrinos>.
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