= Solution
The <gravitational lensing> <mass> includes <dark matter>, hot intracluster gas, stars, and any other material in the projected aperture. Most is not stellar: in the literal convention above the stellar fraction is only $2.22\times10^{12}/(5.89\times10^{14})\simeq0.00376$.
Assume the cluster shares the cosmic <cosmic baryon fraction>, $f_b=\Omega_b/\Omega_m=1/6$, and compare the same aperture for all components. Then
$$
M_b\simeq\frac16M_E=9.82\times10^{13}M_\odot,\qquad
\boxed{M_{\rm gas}\simeq\frac16M_E-M_*\simeq9.60\times10^{13}M_\odot.}
$$
Neglecting stars entirely would give $9.82\times10^{13}M_\odot$. Thus the assumed hot gas dominates the <baryonic matter>, and the remainder $M_{\rm DM}\simeq(5/6)M_E=4.91\times10^{14}M_\odot$ is <dark matter>. The budget is consistent: stars are about $2.26\%$ of the inferred <baryonic matter>, and all components sum to $M_E$.
For a thermal scale, take gas extent $R_g\simeq2R_E=465\,\mathrm{kpc}$ and mean particle <mass> $\mu m_p$ with $\mu\simeq0.61$ for ionized gas. A simple spherical <virial theorem> estimate with gas binding <energy> $W_g\sim-GM_EM_g/R_g$ and thermal <kinetic energy> $K_g=3M_gk_BT/(2\mu m_p)$ gives
$$
\boxed{T\sim\frac{\mu m_pGM_E}{3k_BR_g}\simeq1.34\times10^8\,\mathrm K,\qquad k_BT\sim12\,\mathrm{keV}.}
$$
This is the scale of a very hot, massive X-ray emitting <galaxy cluster>. The numerical prefactor depends on the radial <mass density> profile, gas distribution and boundary <pressure>; for example an isothermal-sphere estimate $k_BT\sim\mu m_pGM/(2R_g)$ gives about $2.0\times10^8\,\mathrm K$. Moreover $M_E$ is a projected aperture <mass> at $R_E$, whereas the estimate needs a spherical enclosed <mass> at $2R_E$; the given data do not determine that conversion. The quoted <temperature> is therefore an order-of-magnitude estimate, not a uniquely measured value. Nor do the data determine the total gas <mass> outside the <Einstein ring> without a profile. The gas budget above pertains to the matched aperture under the cosmic-fraction assumption.
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