= Solution
The <effective radius> is one tenth of the optical outer <radius>: $R_e\simeq2.13$ kpc. A flat <rotation> <speed> then gives $M_{\rm dyn}(<R_e)\simeq4.9\times10^{10}M_\odot$. Half the <luminosity>, with the same <mass-to-light ratio>, implies $M_{\rm luminous}(<R_e)\simeq4.9\times10^{10}M_\odot$.
$$
\boxed{\text{The inner mass budget does not require a large dark-matter fraction.}}
$$
The concentration of light into a small fraction of the optical <radius> suggests a high-surface-brightness, centrally concentrated disk <galaxy>, plausibly an early-type spiral or lenticular with a substantial bulge. The kinematic and photometric data do not uniquely distinguish those morphologies. Disk geometry, an unknown inclination correction, or a varying stellar <mass-to-light ratio> would alter the exact numerical inner comparison.
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