A sample of water is found to contain $5.85\,\% \left(\frac{w}{w}\right)$ of $AB$ (molecular mass $58.5 \, \text{g/mol}$) and $9.50\,\% \left(\frac{w}{w}\right) XY_2$ (molecular mass $95 \, \text{g/mol}$). Assuming $80\,\%$ ionization of $AB$ and $60\,\%$ ionization of $XY_2$, the freezing point of the water sample is [Given: $K_f$ for water is $1.86 \, \text{K kg mol}^{-1}$. The freezing point of pure water is $273.15 \, \text{K}$, and $A$, $B$, and $Y$ are monovalent ions].