Which of the following is more soluble in ammonia?

Which of the following is a sparingly soluble salt?

The solubility product of $Mg(OH)_2$ is $1.2 \times 10^{-11}$. The solubility of this compound in gram per $100 \ cm^3$ of solution is

Precipitation occurs if the ionic product is ........

The solubility of $CuBr$ is $2 \times 10^{-4} \ mol/L$ at $25 \ ^\circ C$. The $K_{sp}$ value for $CuBr$ is

In $1 \ L$ saturated solution of $AgCl$ $[K_{sp}(AgCl)=1.6 \times 10^{-10}]$,$0.1 \ mol$ of $CuCl$ $[K_{sp}(CuCl)=1.0 \times 10^{-6}]$ is added. The resultant concentration of $Ag^{+}$ in the solution is $1.6 \times 10^{-x}$. The value of $x$ is