Which of the following electronegativity order is incorrect?

Arrange the following solutions in order of their increasing boiling points.

(i) $10^{-4} \mathrm{M} \mathrm{NaCl}$

(ii) $10^{-4} \mathrm{M}$ Urea

(iii) $10^{-3} \mathrm{M} \mathrm{NaCl}$

(iv) $10^{-2} \mathrm{M} \mathrm{NaCl}$

In which of the following complexes the CFSE, $\Delta_o$ will be equal to zero?

Which of the following acids is a vitamin ?