Eosin used to detect the end point of precipitation titration by adsorption is called:

An aqueous solution of oxalic acid dihydrate contains $6.3 \ g$ in $250 \ mL$. The volume of $0.1 \ N \ NaOH$ required to completely neutralize $10 \ mL$ of this solution is $.............. \ mL$.

$3.92 \, g$ 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.

When $10 \ mL$ of an aqueous solution of $Fe^{2+}$ ions was titrated in the presence of dil $H_{2}SO_{4}$ using diphenylamine indicator,$15 \ mL$ of $0.02 \ M$ solution of $K_{2}Cr_{2}O_{7}$ was required to get the end point. The molarity of the solution containing $Fe^{2+}$ ions is $X \times 10^{-2} \ M$. The value of $x$ is $....$ (Nearest integer)

Given below are two statements :
Statement $I$ : Potassium hydrogen phthalate is a primary standard for standardisation of sodium hydroxide solution.
Statement $II$ : In this titration,phenolphthalein can be used as an indicator.
In the light of the above statements,choose the most appropriate answer from the options given below:

In a titration experiment,$10 \, mL$ of an $FeCl_{2}$ solution consumed $25 \, mL$ of a standard $K_{2}Cr_{2}O_{7}$ solution to reach the equivalence point. The standard $K_{2}Cr_{2}O_{7}$ solution is prepared by dissolving $1.225 \, g$ of $K_{2}Cr_{2}O_{7}$ in $250 \, mL$ water. The concentration of the $FeCl_{2}$ solution is closest to $..... \, N$
[Given : molecular weight of $K_{2}Cr_{2}O_{7} = 294 \, g \, mol^{-1}$]