Correct order of basic strength of the following oxides

$\text{ Basic strength }\propto \frac{1}{\text{ Oxidation state }}\propto \frac{1}{\text{ E. N. }}$

$\therefore \stackrel{+1}{{\mathrm{K}}_2\mathrm{O}}>\stackrel{+2}{\mathrm{MnO}}>\stackrel{+2}{\mathrm{NO}}>\stackrel{+6}{{\mathrm{SO}}_3^{+2}}$

$\text{ Here }{\mathrm{K}}_2\mathrm{O}\text{ is more basic than }\mathrm{MnO}\text{; }$

MnO is more basic than NO because E.N. of N is more than Mn and less the oxidation state more will be basic character.