Which of the following is least soluble in water?

What will be the solubility of $AlCl_3$ in a solution of $CaCl_2$ with concentration $C$?

The conductivity of a saturated solution of $BaSO_4$ is $3.06 \times 10^{-6} \ \Omega^{-1} \ cm^{-1}$ and its equivalent conductance is $1.53 \ \Omega^{-1} \ cm^{2} \ equivalent^{-1}$. The $K_{sp}$ of the $BaSO_4$ will be

The solubility product of a sparingly soluble salt $AX$ is $4.9 \times 10^{-13}$. What is its solubility in $mol \ dm^{-3}$?

The solubility product of a sparingly soluble salt $AX_2$ is $3.2 \times 10^{-8}$. What is its solubility (in $mol \ dm^{-3}$)?

The $K_{SP}$ of $AgI$ is $1.5 \times 10^{-16}$. On mixing equal volumes of the following solutions,precipitation will occur only with: