Which of the following compounds does not dissolve in ammonium hydroxide solution?

Equal volumes of $0.02 \ M$ $CaCl_2$ and $0.00004 \ M$ $Na_2SO_4$ solutions are mixed. Will a precipitation of $CaSO_4$ occur? $(K_{sp} = 2.4 \times 10^{-5})$

Assign $A$,$B$,$C$,$D$ from the given type of reaction.
$Ag_2CO_3 \downarrow + 2HCl \longrightarrow 2AgCl \downarrow + CO_2 \uparrow + H_2O$

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:

For a sparingly soluble strong electrolyte $AgIO_3$ (molar mass = $283 \, g/mol$),the equilibrium in a saturated solution is given by $AgIO_3(s) \rightleftharpoons Ag^+(aq) + IO_3^-(aq)$. If the solubility product constant $K_{sp}$ of $AgIO_3$ at a given temperature is $1.0 \times 10^{-8}$,how many grams of $AgIO_3$ are contained in $100 \, mL$ of its saturated solution?

The values of $K_{sp}$ for $CuS$,$Ag_2S$ and $HgS$ are $10^{-31}$,$10^{-42}$ and $10^{-54}$ respectively. The correct order of their solubility in water is