Which is not a method to prepare $H_2O_2$?

With reference to the redox properties of hydrogen peroxide $(H_2O_2)$,which of these reactions are feasible?
$(I)$ $2Fe^{2+} + 2H^{+} + H_2O_2 \longrightarrow 2Fe^{3+} + 2H_2O$
$(II)$ $2MnO_4^{-} + 6H^{+} + 5H_2O_2 \longrightarrow 2Mn^{2+} + 8H_2O + 5O_2$
$(III)$ $2Fe^{2+} + H_2O_2 \longrightarrow 2Fe^{3+} + 2OH^{-}$
$(IV)$ $2MnO_4^{-} + 3H_2O_2 \longrightarrow 2MnO_2 + 2H_2O + 3O_2 + 2OH^{-}$

Atomic hydrogen reacts with oxygen to give

In which of the following reactions does hydrogen peroxide act as a reducing agent?

The strength of $11.2$ volume solution of $H_2O_2$ is: [Given that molar mass of $H = 1 \ g \ mol^{-1}$ and $O = 16 \ g \ mol^{-1}$]

Calculate the volume strength of $1.5 \ N \ H_2O_2$.