What precipitate is formed when $SnCl_2$ is added to $HgCl_2$?

During the qualitative analysis of a salt with cation $y^{2+}$,the addition of a reagent $(X)$ to an alkaline solution of the salt gives a bright red precipitate. The reagent $(X)$ and the cation $(y^{2+})$ present are respectively .... .

On saturating an aqueous solution of $Cu(II)$,$Pb(II)$,and $Zn(II)$ ions with $H_2S$,which of the following will precipitate?

In the group analysis of cations, $Ba^{2+}$ and $Ca^{2+}$ are precipitated respectively as

Match List-$I$ with List-$II$ :

List-$I$ (Metal Ion)	List-$II$ (Group in Qualitative analysis)
$(a)$ $Mn^{2+}$	$(i)$ Group-$III$
$(b)$ $As^{3+}$	$(ii)$ Group-$IIA$
$(c)$ $Cu^{2+}$	$(iii)$ Group-$IV$
$(d)$ $Al^{3+}$	$(iv)$ Group-$IIB$

Choose the most appropriate answer from the options given below :

Among the following cations,the number of cations which will give characteristic precipitate in their identification tests with $K_4[Fe(CN)_6]$ is :
$Cu^{2+}, Fe^{3+}, Ba^{2+}, Ca^{2+}, NH_4^{+}, Mg^{2+}, Zn^{2+}$