\(1\,\text{g}\) of \( \mathrm{AB_2} \) is dissolved in \(50\,\text{g}\) of a solvent such that \( \Delta T_f = 0.689\,\text{K} \). When \(1\,\text{g}\) of \( \mathrm{AB} \) is dissolved in \(50\,\text{g}\) of the same solvent, \( \Delta T_f = 1.176\,\text{K} \). Find the molar mass of \( \mathrm{AB_2} \). Given \( K_f = 5\,\text{K kg mol}^{-1} \). \((\textit{Report to nearest integer.})\) Both \( \mathrm{AB_2} \) and \( \mathrm{AB} \) are non-electrolytes.

A ladder of fixed length \( h \) is to be placed along the wall such that it is free to move along the height of the wall.
Based upon the above information, answer the following questions:
(iii) (b) If the foot of the ladder, whose length is 5 m, is being pulled towards the wall such that the rate of decrease of distance \( y \) is \( 2 \, \text{m/s} \), then at what rate is the height on the wall \( x \) increasing when the foot of the ladder is 3 m away from the wall?