Which of the following has the highest boiling point?

The order of ease of dehydration of the following alcohols is:
$I$: $CH_3-CH_2-CH_2-OH$
$II$: $(CH_3)_2CH-OH$
$III$: $(CH_3)_3C-OH$
$IV$: $CH_3-CH_2-OH$

Which of the following reactions takes place when tertiary butanol is passed over heated copper at $573 \ K$?

Identify the product of the following reaction: $CH_3-CH(O)CH_2 \xrightarrow[(ii) H_2O]{(i) CH_3MgBr} ?$

During the dehydration of alcohols to alkenes by heating with conc. $H_2SO_4$,the initiation step is:

In the reaction $CH_2OH-CHOH-CH_2OH + COOH-COOH \xrightarrow{110^\circ C} (A)$,product $(A)$ will be: