$AgCl$ on fusion with $Na_2CO_3$ forms

$1 \text{ mole of } H_2C_2O_4 \text{ is oxidised by } x \text{ mole of } MnO_4^- \text{ in strong basic medium and } 1 \text{ mole of } NaHC_2O_4 \text{ is oxidised by } y \text{ mole of } MnO_4^- \text{ in acidic medium. Ratio of } x/y \text{ is}$

Assign $A$,$B$,$C$,$D$ from the given type of reaction.
$KNO_2 + AgF \longrightarrow AgNO_2 \downarrow + KF$

Assign $A$,$B$,$C$,$D$ from the given type of reaction.
$Na_3PO_4 + Fe_2(SO_4)_3 \longrightarrow FePO_4 \downarrow + Na_2SO_4$

Assign $A, B, C, D$ from the given type of reaction.
$KI + BiI_3 \downarrow \longrightarrow K[BiI_4]$

Purple solution of $KMnO_4 \xrightarrow{Na_2SO_4, BaCl_2}$ Pink ppt. Select the correct statement about pink ppt.