Molar Solubility

By experiment, it is found that of 6.2 x 10$^{-12}$ moles of Pb$_3$(PO$_4$)$_2$ dissolves in 1 L of aqueous solution at 25$^\circ$C. What is the solubility product constant, K$_{sp}$, at this temperature?

What are the concentrations of the ionic species in a saturated solution of Ag$_2$CrO$_4$

K$_{sp}$ = 1.1 x 10$^{-12}$

Calculate the equilibrium concentration of Pb$^{2+}$, I$^-$, Na(\^+$, and NO$_3^-$when 100.0 mL of 0.0500 M Pb(NO$_3$)$_2## and 200.0 mL of 0.100 M NaI are mixed.

PbI$_2$ K$_{sp}$ = 1.4 x 10$^{-8}$

What is the molar solubility of Ag$_2$CrO$_4$ in 0.100 M AgNO$_3$? Compare this to the molar solubility of Ag$_2$CrO$_4$ in water, 1.3 x 10$^{-4}$ M

Ag$_2$CrO$_4$ K$_{sp}$ = 9.0 x 10$^{-12}$