= Solution
The positive $\Delta S^\ddagger=+40\,\mathrm{J\,K^{-1}\,mol^{-1}}$ is compatible with fragmentation/desolvation in the elimination route. A simple rate-limiting association of <hydroxide> with a neutral <ester> would usually have a less favorable <activation entropy>.
The measured activation parameters belong to the overall second-order rate constant: the acid-base pre-equilibrium and solvent reorganization contribute as well. Consequently positive <activation entropy> supports the fragmentation interpretation together with the leaving-group slope, but does not by itself prove a particular elementary transition structure.
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