Which of the following compounds has the highest boiling point?

In the reaction sequence:
$\text{Ethanol}$ $\xrightarrow{PCl_5} X$ $\xrightarrow{\text{alc. } KOH} Y$ $\xrightarrow[H_2O, \Delta]{H_2SO_4, \text{room temp.}} Z$
The product $Z$ is:

What are alcoholic beverages made of?

From the following, how many compounds contain at least one secondary alcohol? Choose the correct answer from the options given below:

Why is sulphuric acid not used during the reaction of alcohols with $KI$?

Identify $Z$ in the following reaction sequence:
$C_2H_5OH$ $\xrightarrow{PBr_3} X$ $\xrightarrow{KOH(alc.)} Y$ $\xrightarrow[(ii) H_2O, \Delta]{(i) H_2SO_4} Z$