In drinking water, if the maximum prescribed concentration of copper is $x \mathrm{mgdm}^{-3}$, the maximum prescribed concentration of zinc will be

The empirical formula of the compound ' $D$ ' formed in the given reaction sequence is

$$ \mathrm{C}_2 \mathrm{H}_4 \xrightarrow{\mathrm{Br}_2 / \mathrm{CCl}_4} A \xrightarrow[\text { (ii) } \mathrm{NaNH}_2]{\text { (i) } \mathrm{Alc} \cdot \mathrm{KOH}} B \xrightarrow[\text { polymerisation }]{\text { Cyclic }} C \xrightarrow[\text { DryAlCla }{ }_3 \text {, dark.cold }]{\mathrm{Cl}_2 \text { (excess) }} $$

Which one of the following mixtures can be separated by steam distillation technique?

$$ \text { The IUPAC name of the following compound is } $$