How many number of reagents can be used to convert ${\mathrm{CH}}_3\mathrm{CHO}$ into respective carboxylic acid or its salt.

$\left(\mathrm{i}\right) \mathrm{Ag}{\left({\mathrm{NH}}_3\right)}_2\mathrm{OH}$

$\left(\mathrm{ii}\right) {\mathrm{CuSO}}_4(\mathrm{Aq}.)+$ Roschell salt

$\left(\mathrm{iii}\right) \frac{{\mathrm{H}}^{+}}{{\mathrm{KMnO}}_4}$

$\left(\mathrm{iv}\right) \frac{ \mathrm{Cu}}{\mathrm{\Delta }}$

$\left(\mathrm{v}\right) {\mathrm{LiAlH}}_4$

$\left(\mathrm{vi}\right) \frac{{\mathrm{K}}_2{\mathrm{Cr}}_2{\mathrm{O}}_7}{{\mathrm{H}}^{+}}$

$\left(\mathrm{vii}\right) {\mathrm{B}}_2{\mathrm{H}}_6+\mathrm{THF}; {\mathrm{H}}_2\mathrm{O}$

$\left(\mathrm{viii}\right) {\mathrm{CH}}_3\mathrm{MgBr}; {\mathrm{H}}_2\mathrm{O}$