$A$ precipitate of calcium oxalate will not dissolve in

The $K_{sp}$ of $AgCl$ at $18\, ^oC$ is $1.8 \times 10^{-10}$. If the concentration of $Ag^{+}$ is $4 \times 10^{-3}\ mol/L$,what is the minimum concentration of $Cl^{-}$ required for $AgCl$ precipitation?

The solubility product of $PbS$ is $3.4 \times 10^{-28}$. If $[Pb^{2+}] = 1 \times 10^{-2} \ mol/L$,what concentration of $[S^{2-}]$ is required to precipitate $PbS$?

The solubility of sparingly soluble salt $AB_2$ is $1.0 \times 10^{-4} \ mol \ dm^{-3}$. What is its solubility product?

The molar solubility $(mol \ L^{-1})$ of a sparingly soluble salt $MX_4$ is $s$. The corresponding solubility product is $K_{sp}$. $s$ is given in terms of $K_{sp}$ by the relation:

The solubility products of $Al(OH)_3$ and $Zn(OH)_2$ are $8.5 \times 10^{-23}$ and $1.8 \times 10^{-14}$ at room temperature. If the solution contains $Al^{3+}$ and $Zn^{2+}$ ions,the ion first precipitated by adding $NH_4OH$ is