Which of the following equations represents the relation between solubility and solubility product for salt $BA_3$?

Which is the correct representation of the solubility product constant of $Ag_2CrO_4$?

If the solubility product of $PbS$ is $3.4 \times 10^{-28}$,what is the minimum concentration of sulfide ions required to precipitate $PbS$ from a $0.001 \ M \ Pb^{2+}$ solution?

Using the Gibbs energy change,$\Delta G^{o} = +63.3 \ kJ \ mol^{-1}$,for the following reaction in water at $25 \ ^{\circ}C$,calculate the solubility product constant $(K_{sp})$:
$Ag_{2}CO_{3(s)} \rightleftharpoons 2Ag^{+}_{(aq)} + C{O_{3}}^{2-}_{(aq)}$
$(R = 8.314 \ J \ K^{-1} \ mol^{-1})$

Solid $Ba(NO_3)_2$ is gradually dissolved in a $1.0 \times 10^{-4} \ M \ Na_2CO_3$ solution. At which concentration of $Ba^{2+}$,precipitate of $BaCO_3$ begins to form? ($K_{sp}$ for $BaCO_3 = 5.1 \times 10^{-9}$)

If the solubility of lithium sodium hexafluoroaluminate $Li_3Na_3(AlF_6)_2$ is $S \ mol/L$,then its solubility product $K_{sp}$ is equal to?