What is the maximum number of moles of electrons taken up by one mole of $NO_3^-$ when it is reduced to the given products?

In the following reaction,identify the oxidation states of the underlined phosphorus atoms in the products formed by complete hydrolysis at $R.T.$:
$H_4\underline{P}_2O_6 + H_2O \longrightarrow H_3PO_3 + H_3PO_4$

Match the reactions in Column $I$ with the nature of the reactions/type of the products in Column $II$.

Column $I$	Column $II$
$A$. $O_2^{-} \rightarrow O_2 + O_2^{2-}$	$p$. redox reaction
$B$. $CrO_4^{2-} + H^{+} \rightarrow$	$q$. one of the products has trigonal planar structure
$C$. $MnO_4^{-} + NO_2^{-} + H^{+} \rightarrow$	$r$. dimeric bridged tetrahedral metal ion
$D$. $NO_3^{-} + H_2SO_4 + Fe^{2+} \rightarrow$	$s$. disproportionation

Assign $A, B, C, D$ for the given type of reaction:
$Mn(NO_3)_2 + 2NaOH \longrightarrow Mn(OH)_2 \downarrow + 2NaNO_3$

Number of moles of $MnO_4^{-}$ required to oxidise one mole of ferrous oxalate completely in acidic medium will be $:-$ (in $mole$)

To measure the quantity of $MnCl_2$ dissolved in an aqueous solution,it was completely converted to $KMnO_4$ using the reaction,
$MnCl_2 + K_2S_2O_8 + H_2O \longrightarrow KMnO_4 + H_2SO_4 + HCl$ (equation not balanced).
Few drops of concentrated $HCl$ were added to this solution and gently warmed. Further,oxalic acid $(225 \ mg)$ was added in portions till the colour of the permanganate ion disappeared. The quantity of $MnCl_2$ (in $mg$) present in the initial solution is . . . . . . . . . (Atomic weights in $g \ mol^{-1}: Mn = 55, Cl = 35.5$ )