Arrange the following compounds as asked: (a) in decreasing order of pK_b values C_2 H_5 NH_2,( C_2 H_5)_2 NH, C_6 H_5 NHCH_3, C_6 H_5 NH_2 (b)…

Arrange the following compounds as asked :

in decreasing order of $\displaystyle \mathrm{pK}_{\mathrm{b}}$ values $\displaystyle \mathrm{C}_{2} \mathrm{H}_{5} \mathrm{NH}_{2},\left(\mathrm{C}_{2} \mathrm{H}_{5}\right)_{2} \mathrm{NH}, \mathrm{C}_{6} \mathrm{H}_{5} \mathrm{NHCH}_{3}, \mathrm{C}_{6} \mathrm{H}_{5} \mathrm{NH}_{2}$

increasing order of boiling point $\displaystyle \mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH}, \mathrm{C}_{2} \mathrm{H}_{5} \mathrm{NH}_{2},\left(\mathrm{CH}_{3}\right)_{2} \mathrm{NH}$

increasing order of solubility in water $\displaystyle \mathrm{C}_{6} \mathrm{H}_{5} \mathrm{NH}_{2},\left(\mathrm{C}_{2} \mathrm{H}_{5}\right)_{2} \mathrm{NH}, \mathrm{C}_{2} \mathrm{H}_{5} \mathrm{NH}_{2}$