The solubility of anhydrous $AlCl_3$ and hydrous $AlCl_3$ in diethyl ether are $S_1$ and $S_2$ respectively. Then:

$A$ $\xleftarrow{CH_3OH, CH_3O^{-}}$ ($1$-methyl$-6-$oxabicyclo[$3.1$.$0$]hexane) $\xrightarrow{CH_3OH, H_2SO_4}$ $B$
$A$ $\&$ $B$ are :

Scheme $1$ and $2$ describe the conversion of $P$ to $Q$ and $R$ to $S$,respectively. Scheme $3$ describes the synthesis of $T$ from $Q$ and $S$. The total number of $Br$ atoms in a molecule of $T$ is. . . . . . . .

The increasing order of the boiling points for the following compounds is
$C_2H_5OH$ $(I)$,$C_2H_5Cl$ $(II)$,$C_2H_5CH_3$ $(III)$,$C_2H_5OCH_3$ $(IV)$

The major product in the following reaction sequence is:

For the compounds:
$(A)$ $H_3C-CH_2-O-CH_2-CH_2-CH_3$
$(B)$ $H_3C-CH_2-CH_2-CH_2-CH_3$
$(C)$ $CH_3-CH_2-CO-CH_2-CH_3$
$(D)$ $H_3C-CH(OH)-CH_2-CH_2-CH_3$
The increasing order of boiling point is:
Choose the correct answer from the options given below: