Which of the following reactions involves both oxidation and reduction?

In neutral or alkaline solution,$MnO_{4}^{-}$ oxidises thiosulphate to.

The equivalent weight of $Na_2S_2O_3$ (Gram molecular weight $= M$) in the given reaction is $I_2 + 2Na_2S_2O_3 \rightarrow 2NaI + Na_2S_4O_6$.

In the reaction $2CuSO_4 + 4KI \rightarrow Cu_2I_2 + 2K_2SO_4 + I_2$,what is the ratio of the equivalent weight of $CuSO_4$ to its molecular weight?

Find the values of $x$ and $y$ for the following balanced equation:
$5H_2O_2 + xClO_2 + 2OH^- \to xCl^- + yO_2 + 6H_2O$

$A_2O_x$ is oxidised to $AO_3^-$ by $MnO_4^-$ in acidic medium. If $1.5 \times 10^{-3} \text{ mole of } A_2O_x$ requires $40 \text{ mL}$ of $0.03 \text{ M } KMnO_4$ solution in acidic medium,which of the following statement$(s)$ is/are correct?