Which of the following salts is insoluble in water?

How many grams of $CaC_2O_4$ (molecular mass $= 128$) on dissolving in one litre distilled water will give a saturated solution (in $g$)? $[K_{sp}(CaC_2O_4) = 2.5 \times 10^{-9} \ mol^2 \ L^{-2}]$

At $T(K)$ in a saturated solution of $MgCO_3$ and $Ag_2CO_3$, if the concentration of $Mg^{2+}$ ion is $3.2 \times 10^{-5} \ M$, then the concentration of $Ag^{+}$ ion in the solution will be [Given: $K_{sp}(MgCO_3) = 1.6 \times 10^{-6}$ and $K_{sp}(Ag_2CO_3) = 8.0 \times 10^{-12}$ at $T(K)$]

The solubility of $AgCl$ is $1.43 \times 10^{-3} \ g/L$. If the molar mass of $AgCl$ is $143 \ g/mol$,then the solubility product $(K_{sp})$ is:

The solubility product of $AgI$ at $25\,\text{°C}$ is $1.0 \times 10^{-16}\,\text{mol}^2\,\text{L}^{-2}$. The solubility of $AgI$ in $10^{-4}\,\text{N}$ solution of $KI$ at $25\,\text{°C}$ is approximately (in $\text{mol L}^{-1}$)

The solubility product of $PbCl_2$ at $298 \ K$ is $1 \times 10^{-6}$. Its solubility in $mol/L$ is: