Which of the following equations represents the solubility product $(K_{sp})$ of $As_2S_3$?

An aqueous solution contains $SCN^{-}$,$Br^{-}$,$I^{-}$,and $Cl^{-}$ ions. When $AgNO_3$ is added to the solution,which of these will precipitate first? Given: $K_{sp}(AgCl) = 1.2 \times 10^{-10}$,$K_{sp}(AgI) = 1.7 \times 10^{-16}$,$K_{sp}(AgSCN) = 7.1 \times 10^{-7}$,$K_{sp}(AgBr) = 3.5 \times 10^{-13}$.

At $298 \ K$,the solubility of silver chloride in water is $1.434 \times 10^{-3} \ g \ L^{-1}$. The value of $-\log K_{sp}$ for silver chloride is $........$ (Given: molar mass of $Ag = 107.9 \ g \ mol^{-1}$ and $Cl = 35.5 \ g \ mol^{-1}$)

If $H_2S$ is passed in a solution of $0.1 \ M \ Zn^{2+}$ and $0.01 \ M \ Cu^{+}$ and the concentration of $S^{2-}$ is made $8.1 \times 10^{-31} \ M$. Which precipitation of $ZnS$ and $CuS$ will take place? Given: $K_{sp}(ZnS) = 3.0 \times 10^{-23}$ and $K_{sp}(CuS) = 8.0 \times 10^{-34}$.

For a sparingly soluble salt $A_pB_q$,what is the relationship between its solubility $(S)$ and solubility product $(K_{sp})$?

Assign $A$,$B$,$C$,$D$ from the given type of reaction.
$Ba(AcO)_2 + K_2CrO_4 \longrightarrow BaCrO_4 \downarrow + 2AcOK$