While titrating a dilute $HCl$ solution with an aqueous $NaOH$ solution,which of the following will not be required?

$3.92 \, g$ of ferrous ammonium sulfate crystals are dissolved in $100 \, mL$ of water. During titration,$20 \, mL$ of this solution is required for complete oxidation by $18 \, mL$ of $KMnO_4$ solution. Calculate the weight of $KMnO_4$ in $1 \, L$ of the solution in grams.

$20 \, mL$ of $0.02 \, M$ hypo solution is used for the titration of $10 \, mL$ of copper sulphate solution,in the presence of excess of $KI$ using starch as an indicator. The molarity of $Cu^{2+}$ is found to be $\times 10^{-2} \, M$ [nearest integer]. Given: $2 Cu^{2+} + 4 I^{-} \rightarrow Cu_{2}I_{2} + I_{2}$ and $I_{2} + 2 S_{2}O_{3}^{2-} \rightarrow 2 I^{-} + S_{4}O_{6}^{2-}$.

$40 \ mL$ of a mixture of $CH_3COOH$ and $HCl$ (aqueous solution) is titrated against $0.1 \ M$ $NaOH$ solution conductometrically. Which of the following statements is correct?

In the titration of $KMnO_{4}$ with $C_{2}O_{4}^{2-}$,which temperature range is not proper? Why?

During the estimation of oxalic acid $V/S$ $KMnO_4$,the self-indicator is: