What is the range of number of carbon atoms in alkanes found in paraffin wax?

Which of the following amines is most basic in nature in aqueous phase?

Which of the following $0-10 \mathrm{~m}$ aqueous solutions will have maximum $\Delta T_f$ value?

If boiling point of urea solution is $100.18^{\circ} \mathrm{C}$ and $K_b$ for water is $0.512 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}$, molality of solution is (Boiling point of water $=100^{\circ} \mathrm{C}$)